



































Shop Equipment—Hand 
Forging—Tool Dressing 



BLACKSMITH-SHOP EQUIPMENT 
HAND FORGING 
TOOL DRESSING 


> ) 
) ) ) 



T7 H 


205 

Published by 

INTERNATIONAL TEXTBOOK COMPANY 

SCRANTON. PA. 

ini’ 


XX'zib 


I 


Blacksmith-Shop Equipment: Copyright, 1915, 1906, by International Textbook 
Company. 

Hand-Forging, Part 1: Copyright, 1915, by International Textbook Company. 

Hand Forging, Part 2: Copyright, 1915, 1906, by International Textbook Com¬ 
pany. 

Tool Dressing: Copyright, 1916, 1906, by International Textbook Company. 


Copyright in Great Britain 


All rights reserved 


Printed in U. S. A. 


CjCMJO * t (o 




International Textbook Press 
Scranton Pa. 


74943 





CONTENTS 


Note.—T his book is made up of separate parts, or sections, as indicated by 
their titles, and the page numbers of each usually begin with 1. In this list of 
contents the titles of the parts are given in the order in which they appear in 
the book, and under each title is a full synopsis of the subjects treated. 

BLACKSMITH-SHOP EQUIPMENT Pages 
Heating Devices. 1-25 

Forges .\. 1-18 

Stationary forges; Production of blast; Disposal of 
smoke and gases; Portable forges. 

Forge Fuels and Fire. 19-25 

Fuels; Fire and fire tools. 

Blacksmithing Tools. 26-52 

Anvil . 26-27 

Hand Tools . 28-35 

Hammers and sledges; Forming and cutting tools; 

Tongues. 

Bench and Floor Tools. 36-52 

HAND FORGING, PART 1 

Manufacture of Iron. 1-11 

Cast Iron. 1 

Wrought Iron. 2- 4 

Low-Carbon Steel. 5-11 

Forging Operations. 12-37 

Definitions and General Directions. 12-14 

Drawing. 15-19 

Bending . 20-23 

Twisting. 24-26 

Upsetting. 27-36 

Shrinking. 37 




















IV 


CONTENTS 


HAND FORGING, PART 2 Pages 

Forging Operations—(Continued). 1-35 

Right-Angled Bends. 1- 4 

Welding. 5-35 

Conditions governing welding; Classification of welding; 

Work involving scarf welds; Work involving butt 
welds; Miscellaneous examples of welding. 

TOOL DRESSING 

Tool Steels . 1-11 

Methods of Manufacture. 1-2 

Temper and Treatment of Tool Steel. 3-11 

Examples of Tool Dressing. 12-47 

Carbon-Steel Tools. 12-34 

Chisels and hammers; Lathe, planer, and slotter tools; 

Flat drills; Springs; Steeling; Special tools. 

High-Speed Steel Tools. 35-47 











BLACKSMITH-SHOP EQUIPMENT 

Serial 1686 Edition 1 


HEATING DEVICES 


FORGES 


STATIONARY FORGES 

1. A forge is an open fireplace, or hearth, with forced 
draft, arranged for heating iron, steel, and other materials. 
A very serviceable form of brick Jorge is shown in Fig. 1. The 
hearth is usually rectangular in shape, and 26 or 28 inches in 
height. For ordinary work, the front a b may be from 2§ to 
3 feet long, and the side b c from 3 to 4 feet long. An iron water 
trough 6 to 8 inches wide is often fastened along the side b c. 
The brickwork is usually built with a space / in the top, for the 
fire and fuel. The depth of this space varies greatly, according 
to the work and the idea of the workman, but it is usually 
from 4 to 8 inches; the bottom consists either of brickwork or 
of an iron plate, supported on bars. 

2. The forge is usually provided with a hood to catch the 
smoke and lead it into the stack or chimney; Fig. 1 shows a 
sheet-iron conical hood attached to the chimney, but the hood 
may be square and is sometimes built of brick. 

Where there is plenty of room in the smith shop and the 
blast is supplied by hand power, the brick forge is frequently 
used. The advantages claimed for it are that it is little affected 
by the moisture of the atmosphere, costs less for repairs than 

COPYRIGHTED BY INTERNATIONAL textbook COMPANY. ALL RIGHTS RESERVED 

§48 





2 


BLACKSMITH-SHOP EQUIPMENT 


48 


the iron forge, and the form of the hearth may be quickly and 
easily changed to suit the requirements of the various classes 
of work. 

3. Forge Tuyeres. —The bottom of the forge shown in 
Fig. 1 has a suitable opening cut in it, in which is fitted a 



Fig. 1 


tuyere iron (pronounced tweer iron), sometimes called an 
air chamber, or a wind box, for the purpose of admitting 
air under the fire. The bottom of the tuyere iron has an 
opening about the same size as that cut in the bottom of the 
forge. This opening is closed by a valve of thin sheet iron by 
means of the handle 5. 














































































































48 


BLACKSMITH-SHOP EQUIPMENT 


3 


In Fig. 2 is shown a section of one form of tuyere iron com¬ 
monly used. It has an opening j in one side, and one g in its 
top. The side opening is connected with a pipe through which 
air is supplied to the fire. The top opening is usually capped 
with a nozzle b, and fitted with a valve c. The valve is so made 
that it will admit air to the fire and permit the cinders to drop 
into the bottom of the tuyere iron. The cinders are dropped 
into a cinder pit by opening the valve /, which is hinged at h 
and operated by the rod k. 

4. The nozzle v, Fig. 1, or b, Fig. 2, with the valve c at the 
top of the tuyere iron, is called the tuyere. The valve is 



controlled by the handle shown at k, Fig. 1. A separate valve 
not shown in Fig. 2 but shown at /, Fig. 5, controls the amount 
of the opening for the air supply. The top of the tuyere is 
usually so placed that it comes 3 or 4 inches below the level of 
the top of the brickwork abed, Fig. 1, and from 12 to 15 inches 
in front of the chimney. The bottom of the fire space is 
occasionally covered with clay hollowed into a cup shape around 
the tuyere. In doing this, care must be taken to work, or 
temper, the clay to a proper consistency, for the stiffer it is, the 
less it will shrink and crack. Strong brine is often used to 
moisten the clay, as it keeps the bed from burning out too 
















4 


BLACKSMITH-SHOP EQUIPMENT 


§48 


quickly. The space about the tuyere is also sometimes packed 
with cinders to the level of the tuyere. Suitable space is 

provided in the forge bottom 
for the free movement of the 
handles k and which are 
sometimes incased in pieces 
of wrought-iron pipe. 

5. A cheaper and simpler 
style of tuyere than the one 
shown in Fig. 2 is shown in 
Fig. 3. The dish-shaped 
nozzle b has a circular hole 
in the bottom, below which 
is the valve c. By turning 
the rod d, the valve c is 
brought into different posi¬ 
tions, thus increasing or 
diminishing the opening. The 
blast enters through the pipe 
j. The tube e is closed at the lower end by the shutter / so 
that when cinders have collected in e, the shutter / is opened 





Fig. 4_ y 

by means of the rod k and the cinders are dropped out with¬ 
out disturbing the fire. 















































































48 BLACKSMITH-SHOP EQUIPMENT 5 


6. Combination Forge. —A combination brick and iron 
forge is sometimes made, as shown in Fig. 4, by supporting a 
frame a of 2-inch or 3-inch angle iron, about 3J or 4 feet by 
6 feet, on angle-iron legs b. The bottom is formed of §"X2" 
iron strips, supporting a layer of common red brick c. The 
tuyere d is attached to two of the |-inch iron strips, and the 
hearth is covered with clay or cinders. 

7. Iron Forge. —The iron forge is made with a cast-iron 
bowl supported on legs. The tuyere iron is fastened in the 
bottom of the bowl and the air blast is supplied either from a 
stationary blower, or bellows, or from a small blower secured 
to the forge. The blower may be driven by a crank, a treadle, 



or a lever working with a ratchet. Fig. 5 shows an iron forge 
that is suitable for either stationary or portable use. It has 
no hood to obstruct the handling of the work. The blast is 
supplied from a blast pipe or from a small portable blower 
mounted on a separate stand; a is a rest for the tongs or long 
pieces of work; it is supported by the rod b; c is the coal trough 
and d the water trough; e is the top of the tuyere; / is the valve 
in the blast pipe; and g is the cinder valve at the bottom of 
the tuyere iron. 

8. Gas Furnaces. —Gas furnaces are arranged to heat 
the work in one of three ways. The flame may strike directly 
on the work to be heated, it may strike an arched roof from 









































6 


BLACKSMITH-SHOP EQUIPMENT 


§48 


which the heat is reflected on the work, or it may be in a chamber 
more or less completely separated from the work. The furnace 
shown in Fig. 6 is arranged to heat the stock by direct contact 
with the flame. There is a burner at each end of the furnace. 
The one at a directs the flame against the arched roof and the 
one at the opposite end directs the flame against the floor of 



Fig. 6 

the furnace, thus heating all parts of the chamber. Gas is 
led to the burner through the pipe b and air through the pipe c, 
the flow of each being controlled by a valve in the pipe. The 
pressure of the air varies, in different furnaces, from a few 
ounces to a pound or more. Another air pipe d, with a row of 
small holes drilled along the top, extends across the front of 
the furnace. The air that escapes through these holes blows 


















































































































48 


BLACKSMITH-SHOP EQUIPMENT 


7 


across the opening e and keeps the flame from coming out 
beyond the shield /. The shield protects the workman from 
the heat of the furnace and in this case is water-cooled. It is 
built up of two steel plates, which are about 2 inches apart 
so as to form a water space between them. Water enters 
this space through the pipe g and leaves through the pipe h. 
The overflow from the pipe h is sometimes discharged into a 
funnel, so that the rate of flow of the cooling water may easily 
be seen. 

The bottom or hearth of the furnace slopes toward a slag 
spout in the center of the back wall and any slag that may 
be formed is discharged from this spout. The stock is laid on 
the firebricks in the opening e, the part to be heated extending 
into the furnace. The flame from burner a then passes over 
the stock and that from the other burner passes under it. Large 
furnaces are provided with more than one burner on each side. 
When a very high temperature is required, the air may be 
preheated by passing it through pipes in the upper part of the 
furnace before it is taken to the burner. 

9. The furnace just described is suitable for heating stock 
that is to be forged and similar work when a high temperature 
is to be produced, but an absolutely uniform temperature 
throughout the stock is not necessary. When it is necessary 
that the stock be heated uniformly throughout, the heating must 
be done more gradually by separating it more or less com¬ 
pletely from the flame and products of combustion. For such 
work as spring tempering, the flame may be directed against 
the roof of the furnace and the heat reflected downwards on the 
stock. In other cases, the gas is burned in a chamber below 
the heating space and the hot gases pass up into the heating 
space along the side walls. For such work as tool tempering, 
the stock to be heated is placed in a chamber that is entirely 
separated from the flame and products of combustion. 

10. Oil Furnaces. —Furnaces in which oil is burned are 
substantially the same as those for gas, the only difference 
being in the burner. In order to bum oil economically, it must 
be reduced to a fine spray by blowing it into the furnace by 


8 


BLACKSMITH-SHOP EQUIPMENT 


§48 


steam or air. To make it flow freely in the pipe, the oil must 
be under a pressure of 5 pounds or more; but to atomize , or 
spray, the oil, a steam or air pressure at least double the oil 
pressure should be available. Valves should be placed in the 
oil and air, or steam, pipes near the burner so that the proper 
proportions of steam and oil, air and oil, or steam, air, and oil 
may be obtained. When the oil is atomized by steam, air must 
be supplied for the combustion of the oil. Steam that is to be 



used to atomize oil must be dry; that is, it must not contain any 
water. Water in steam that is used to atomize oil will be 
evaporated by the heat of the burning oil and this will cool the 
fire so that the highest temperature that the oil can produce will 
not be available. Dry steam cannot usually be had economi¬ 
cally in the blacksmith shop and oil is therefore commonly 
atomized in furnaces by air under pressure. 

The proportions of air and oil should be adjusted so that the 
flame will be just clear of the end of the burner. If there is 
not enough air to atomize the oil properly, the flame will be 






























































































































48 


BLACKSMITH-SHOP EQUIPMENT 


9 


smoky, it will bum at the end of the burner or possibly inside 
it, and oil may drip from the end of the burner. If, however, 
there is too much air, the flame will be far from the end of the 
burner and it will be more or less cooled, as some of the heat 
will be used to raise the temperature of the excess air. When 
oil is being burned properly, it produces a bright white flame 
without smoke or soot. 

11. Powdered-Coal Furnace. —The furnace in which 
powdered coal is burned is rectangular like oil and gas furnaces 
but unlike them it has a chimney. Three views of a powdered- 
coal furnace are shown in Fig. 7. A top view with the roof 
removed is shown in (a), a view with the front removed is 
shown in (6), and a side view is shown in (c). The powdered 
coal, together with the air for its combustion, is brought into 
the furnace at a in the rear wall and the stock to be heated is 
put into the furnace through the opening b in the front wall. 
The products of combustion are taken off by the flue c leading 
to the chimney d , from which any accumulation of dust is 
removed through the clean-out door e. The hearth / slopes 
toward the opening g in the rear wall where the slag is 
discharged. 

12. The mixture of coal dust and air that is fed to the 
furnace is governed by the controller shown in Fig. 8. The 
controller is attached to the lower end of the conical bin a in 
which the powdered coal is stored. Coal flows into the con¬ 
veyer b which is rotating so as to move it to the left end of the 
controller when it falls through the mixing chamber c. Two 
pipes are attached to the mixing chamber, one at d and the 
other on the opposite side. A current of air enters the mixing 
chamber through one of these pipes and leaves it through the 
other one, picking up and taking with it some of the coal dust. 
Any coal dust that is not taken up by the air-current, falls on 
the conveyer e which returns it to the right-hand end of the 
controller where it is again fed forwards by the conveyer b. 
The conveyer e is arranged so that it is able to return all the 
coal that the conveyer b can supply. In this way the controller 
cannot become clogged even though the air blast is shut off 


§48 


10 BLACKSMITH-SHOP EQUIPMENT 

entirely. The controller shown is driven by the electric 
motor /. 

The mixture of coal dust and air that leaves the controller 
does not contain enough air to burn the coal and additional 
air must therefore be supplied. This additional air is supplied 
at a pressure not greater than 1 or 1| ounces through the pipe h , 
Fig. 7, and the mixture from the controller is introduced into 
the current of auxiliary air through the pipe i leading from the 
controller into the air pipe as shown. In some cases, the coal is led 
into the air pipe at some distance from the furnace so that the 



Fig. 8 


coal and air are thoroughly mixed when the furnace is reached. 

There are three ways in which the mixture of coal dust and 
air that is fed to the furnace may be controlled. The air 
supply to the mixing chamber of the controller may be varied, 
the amount of coal supplied to the mixing chamber may be 
varied by changing the speed of the controller, and the amount 
of auxiliary air may be varied. The air supply is controlled by 
valves or dampers placed in the air pipes, one in the pipe 
through which the air enters the controller and the other in 
the auxiliary air pipe at j. 


















































































































-18 


BLACKSMITH-SHOP EQUIPMENT 


11 


PRODUCTION OF BLAST 

13. Bellows. —The air blast is produced either by means 
of a rotary fan, or blower, or by a bellows. The bellows illus¬ 
trated in Fig. 9 consists of two parts separated by a partition. 
The air from the lower half is forced through the valves / in the 
center board into the upper chamber, where it is stored for use. 
The bellows is hung from the center board by pins m , and as 
the lower board is drawn up, the air in the lower part is forced 
through the valves/ into the upper chamber, inflating it and rais¬ 
ing the top board. As the bottom board descends, the valves/ 
close and the valves c open, allowing air to flow in and fill the 
space below the center board. By placing a weight on the 
top board, the air pressure in the upper part is increased. 



Fig. 9 


14. The top board should be held up when the bellows is 
idle for any great length of time, to keep the leather stretched 
and prevent it from cracking. This may be done by fastening 
the hook /, in a chain suspended from the ceiling. With this 
care, the bellows will last much longer, for if the upper part 
is always folded together when not iq use, the leather will soon 
crack and the upper part will be spoiled while the lower half 
is still in good condition. The operating chain or rod is attached 
to the hook d, and the air from the upper part discharges through 
the tube or nozzle h. The leather of the bellows should be oiled 
two or three times a year with neat’s-foot oil or harness oil to 
preserve it. It should always be oiled before cold weather sets 

205—2 














12 


BLACKSMITH-SHOP EQUIPMENT 


§48 


in, so as to make it pliable during the winter. On a cold 
morning, the bellows should be started slowly, so as not to crack 
the leather while it is stiff with the cold. 

15. Rotary Blower, or Fan. —The rotary blower, or 
centrifugal fan, Fig. 10, has a number of blades set nearly 
radially on the shaft and placed within a cylindrical iron casing, 
with inlet holes d concentric with the shaft on each side, and an 
outlet, opening into the delivery pipe k, at the outer edge of 
the casing. The shaft is driven by a belt passing over a 
pulley e. The rapid rotation of the blades throws the air out¬ 
wards, that is, away from 
the center. The air close 
to the shaft rushes in 
through the opening d , to 
fill the space, and so a 
constant blast is main¬ 
tained. 

16. For small forges, 
hand-driven rotary fans 
are very frequently used. 
There are a number of 
styles on the market driven 
by cranks either through 
trains of gears or through 
belts. These portable 
hand blowers, however, 
are used more in small smith shops than in blacksmith shops 
connected with manufacturing plants. One of their principal 
advantages is that they take up less room than the bellows and 
are in many cases capable of producing a much greater blast 
pressure. A good hand blower should be so constructed that 
it can run in either direction without drawing ashes back into 
it. Power-driven fans may be operated by a belt from a pulley 
on the line shafting, by belting from an electric motor, or by 
direct-connected motor. 

17. Several forms of blast gates are used in the blast 
pipes of power fans. These should be so placed that they may 

















§48 


BLACKSMITH-SHOP EQUIPMENT 


13 


be conveniently operated by the smith while working at the 
forge and set so as to supply the blast to suit the work. There 
are two general styles of gates for controlling the air pressure; 
one is an ordinary damper like that placed in a stovepipe, and 
the other is a slide that can be pushed in or drawn out through 
an opening in the side of the air pipe. 

18. Positive Rotary Blower. —A positive blower differs 
from a fan in that it has two rotating impellers placed with 
their axes parallel and geared together at either one or both 
ends with gears of equal diameters. The impellers have curved 
sides and are so placed that they run together like gears with 
two teeth each. Because of this combination of form and 
arrangement of the im¬ 
pellers, the blast produced 
differs from that of the 
fan previously described. 

This blower delivers a 
definite quantity of air 
under pressure into the 
delivery pipe at each 
revolution of the impel¬ 
lers. Thus the air may 
be forced through an 
opening against resis¬ 
tance, .such as a varying 
amount of cinders, coal, or metal covering a tuyere. A blast 
of this character is called a positive blast, and machines for 
producing it are called positive blowers. 

Fig. 11 is a sectional view of one form of rotary blower taken 
at right angles to the axes of the impellers. The arrows at a 
show the directions of rotation of the impellers, and the direc¬ 
tion of the air at the intake and delivery pipes. This same form 
of blower is sometimes connected to small forges and operated 
by hand. 

19. Water Gauge. —For measuring the blast pressure, a 
water gauge is generally used. A simple form is made of a 
glass tube bent to the shape shown in Fig. 12. The tube is 










14 


BLACKSMITH-SHOP EQUIPMENT 


48 


fastened to a board, and a scale, graduated in inches, is made 
to slide vertically between the two parallel arms of the tube. 
The air pipe, having a stop-cock at s, is then connected at c and 
the end a is left open. Water is poured into the tube until it 

rises to the height d in both tubes. 
The stop-cock 5 is then opened, and 
the air-blast pressure forces the 
water up in tube a ; the scale is 
then moved into position so that 
the zero mark is on a line with the 
water level in the shorter tube, and 
the reading is taken at the level 
of the water in the long arm. 
Ordinarily, a blast of from 4 to 6 
ounces pressure to the square inch, 
or, approximately, 7 to 10 inches 
of water, is used for a blacksmith’s 
forge. A pressure of 1 pound to 
the square inch is equal to the pres¬ 
sure of a column of water 27.7 inches 
high; and the pressure of 1 ounce 
to the square inch is equal to a 
pressure of 1.73 inches of water. 



Fig. 12 


One inch of water corresponds to a pressure of .577 ounce. 
Suppose the water column measures 10 inches, then the pressure 
of the draft is .577X10 = 5.77 ounces. 


DISPOSAL OF SMOKE AND GASES 

20. Hoods and Chimneys.—In the case of a single 
stationary forge like that shown in Fig. 1, the gas and smoke 
from the fire are usually drawn up through the hood by 
the natural draft of the chimney. If the forge stands in the 
center of the room, the hood is sometimes suspended over it 
and connected with a sheet-iron chimney going straight up 
through the roof. The chimney may be provided with some 
form of top that will insure a draft no matter which way the 
wind blows. 






















































48 


BLACKSMITH-SHOP EQUIPMENT 


15 


21. Overhead Exhaust System. — In the overhead 
exhaust system, a hood is hung over each fire and the pipes 
from the hoods are carried to a common exhaust pipe, from 

. which the smoke is drawn by means of a fan. This system 
is positive in its action and gives quite efficient service, but 
the suspended hood and pipes are frequently in the way of 
cranes or other handling devices; they also obstruct the light 
to a certain degree. 

22. Down-Draft System. —The forge shown in Fig. 13 
for the down-draft system is like that for the overhead system 
except in the manner 
in which the smoke is 
removed. The hood 
a is placed at one side 
of the forge and is 
arranged so that it 
may be raised and 
lowered by turning the 
hand wheel b. The 
smoke pipe c connects 
with a flue below the 
floor through which 
the smoke is taken to 
the chimney. This 
system requires two 
fans or their equivalent. One is arranged to supply the blast 
to the fire and the other draws the smoke out through the 
pipe c; the first fan is called a blower and the second an exhauster. 
The layout of forges, fans, and air passages is given in Fig. 14. 
Blast is supplied by the blower a through the duct b below the 
floor. Outlets are taken off at intervals as required by the 
forges c. The hoods d of the forges are tilted over the fires so 
as to catch the smoke. The exhauster e then draws the smoke 
into the smoke duct /. After the smoke passes through the 
exhauster it goes to the chimney. 

23. The exhauster necessarily draws a large amount of 
air into the hood with the smoke. A portion of this mixture 



Fig. 13 


































































































16 


BLACKSMITH-SHOP EQUIPMENT 


48 



of air and smoke is some¬ 
times used in place of a 
fresh-air blast. When 
this is done,, a pressure 
exhauster, which serves 
the purpose of both an 
exhauster and a blower, 
is used. The discharge 
from the exhauster is un¬ 
der a pressure equal to 
that needed for the blast. 
This pressure is main¬ 
tained by an automatic 
valve that opens the out¬ 
let to the chimney only 
when the pressure in the 
discharge pipe from the 
exhauster exceeds the 
desired blast pressure. 
The blast pipe branches 
from the side of the pipe 
leading to the chimney 
at a point between the 
automatic valve and the 
exhauster, so that a part 
of the discharge from 
the exhauster may be 
returned in the blast to 
the forges. The greatest 
advantages of the down- 
draft system are that the 
space above the forge 
is clear for the use of 
cranes, or other handling 
devices, that there are 
no pipes to obstruct the 
light, and the smoke 
flues will not rust. 

















































































§48 


BLACKSMITH-SHOP EQUIPMENT 


17 





tz 


~r 


24. Blast Pipes. —The fan, or blower, should be located 
as close to the forge as possible, and all unnecessary bends in 
the pipe avoided, because there is considerable loss in pressure 
when air is forced through a long pipe or one having abrupt 
bends. All bends should be made in long easy curves. 
Where a large number of forges are supplied with air from one 
fan, or blower, care must be taken to proportion the various 
branches of the pipe system correctly. The fan, or blower, 
must be run at a speed that will give more than 4 ounces pressure 
near the fan, in order to 
allow for the loss of 
pressure in the pipe and 
insure the required 4 
ounces pressure at the 
tuyere. The manufac¬ 
turers of fans and 
blowers furnish tables 
giving the proper sizes 
and proportions of blast 
pipes. 

25. Danger of Ex¬ 
plosion . —Sometimes 
coal gas flows back into 
the blast pipe when the 
fan is not running, form¬ 
ing a mixture of gas and 
air that may explode 
and burst the pipe when 
the fan is started; this is particularly the case if the blast 
pipe is overhead. The danger of explosion may be prevented 
by having one or more valves in the top of the pipe, as 
shown in Fig. 15, to allow the gas to escape. The valve a 
is made of thin sheet iron, and is held up by the blast when the 
fan is running, but drops on cross-wires b and permits the gas 
to escape when the fan is not running. A top view of this valve 
is shown at c; the free opening at the top should be 3 inches or 
more in diameter. 


i 


Fig. 15 





















18 


BLACKSMITH-SHOP EQUIPMENT 


48 


26. Heating- and Ventilation. —The problem of heating 
and ventilating large blacksmith shops is a difficult one. Prob* 
ablv the best way of warming is by hot air blown into the shop 
through numerous openings near the floor. This tends to pro¬ 
vide fresh air near the floor, while the smoke may be removed 
from the upper part of the room either by opening ventilators, 
or overhead windows, or by the use of fans. Sometimes all 

these methods are used 
together. Even under 
the best conditions, it is 
sometimes found diffi¬ 
cult to keep the shop 
warm and free from smoke and 
gases that escape from the forges. 



PORTABLE FORGES 

27. Portable forges are those 
that may be moved about easily 
and are of various forms to meet 
the requirements of special classes 
of work. For example, some work 
might have to be done by black¬ 
smiths, machinists, bridge builders, 
yVj boilermakers, etc. There are many 
kinds of work to which these forges 
are adapted, but they are especially 
useful when work is done away from the shop. 

Fig. 16 shows a portable forge that is much used for heat¬ 
ing rivets. It has a cast-iron bowl a supported on legs made 
of iron pipe. The blast is supplied from a small rotary fan /, 
secured beneath the bowl. This fan is operated by the lever 6, 
connected through a link, as shown, with a second lever d, which 
carries a ratchet on its outer end that engages with ratchet teeth 
on the inside of the gear c. 


Fig. 16 





























BLACKSMITH-SHOP EQUIPMENT 


19 


§48 


FORGE FUELS AND FIRE 


FUELS 

28. Coal.—The fuel that is most commonly used on 
blacksmiths’ forges is bituminous coal, usually called soft 
coal. It is broken into small pieces, and when free from sulphur 
and of good quality is excellent for this purpose. A fuel con¬ 
taining sulphur should be avoided, as it will be absorbed by the 
iron. Sulphur makes the iron hot short, that is, it makes it 
brittle while hot and difficult + o weld. 

Some grades of bituminous coal bum too rapidly, and some 
contain too much earthy matter to give a free-burning, clean 
fire, producing a high temperature. 

Anthracite culm or hard-coal siftings is sometimes used, but 
this fuel is apt to contain more impurities than soft coal. In 
order to use it, careful attention must be given to the blast, 
and in any case it will not make a hollow fire. Blacksmiths 
do not, as a rule, look with very great favor on anthracite as a 
smithing fuel and its use is therefore recommended only when 
a suitable soft coal is not available. 

29. It is advisable to have samples of coal analyzed by a 
competent chemist so that the blacksmith may know the 
quality of the fuel he is using. Coal in its natural state con¬ 
tains some water, which is undesirable because it is evaporated, 
thus taking heat from the fire, and reducing the amount of heat 
that is available and the temperature that can be produced. 
Coal also contains certain compounds, the exact composition of 
which is not usually of particular interest, that are liberated 
as gases when the coal is heated. These compounds are com¬ 
monly grouped together as volatile matter . Some bituminous 
coals seem to fuse, when the volatile matter is driven off, form¬ 
ing a spongy mass called coke. Other bituminous coals fuse 
when the volatile matter is driven off but do not form the 
typical spongy mass of coke; still other bituminous coals do 
not fuse but bum somewhat like charcoal. The volatile matter 



20 


BLACKSMITH-SHOP EQUIPMENT 


48 


bums readily under suitable conditions and gives a large amount 
of heat but it is not possible to burn coal in an open forge so 
that the heat of the volatile matter is available. 

30. Coke.—Coking coal is preferred for use in the forge 
because it does not tend to choke the fire during the coking 
process. The progress of the coking operation is indicated by 
the escape of the volatile matter, which may be seen in the 
blue flame and smoke issuing from the bed of fuel. The 
remaining coke is composed of fixed carbon and ash. Fixed 
carbon is the solid part of coke that is available for the pro¬ 
duction of heat; it is the chief constituent of coke. Ash is the 
incombustible part of coke, and consequently adds nothing to 
the heating value. Practically all of the sulphur in the coal 
will remain in the coke formed from it, though a small amount 
of sulphur may be driven off with the volatile matter. A good 
smithing coal should not contain more than 1 per cent, of 
sulphur and frequently does not contain more than J of 1 per 
cent. A good smithing coal should satisfy the following con¬ 
ditions : Coke should be formed when the volatile matter is 
driven off; volatile matter should be as low as possible; fixed 
carbon should be as high as possible; sulphur should be less 
than 1 per cent; ash should be as low as possible. 

31. Charcoal.—Another solid fuel made by artificial 
means is charcoal. It is the best fuel because of the small 
amount of impurities that it contains. It is an excellent fuel 
for heating carbon steels, giving a clean fire, free from sulphur 
and other objectionable matter. A charcoal fire is, however, 
not suitable for heating high-speed steels, as it is impossible 
to get the high temperature required. Charcoal made of maple 
or other hard wood is the best. Some manufacturers of twist 
drills, reamers, milling, and other cutting tools, use charcoal 
exclusively. The objections to this fuel are that its cost is 
high and that it heats the work more slowly than coal. 

32. Gas.—There are four kinds of gas that may be used 
as fuel in the blacksmith shop. They are natural gas, coal, or 
illuminating, gas, producer gas, and water gas. Natural gas 


48 


BLACKSMITH-SHOP EQUIPMENT 


21 


comes from wells in certain parts of the country and its use 
is limited to the immediate vicinity of the wells. Natural gas 
that is to be used in the blacksmith shop must not contain an 
excessive amount of sulphur, especially if the iron that is being 
heated comes into contact with the products of combustion or 
the flame. Coal gas, or illuminating gas, is the volatile matter 
driven off by heating coal. This kind of gas is not usually 
available at a sufficiently low price to make it an economical 
shop fuel. Producer gas is made by burning coal in an apparatus 
called a producer in such a manner that the resulting gases are 
themselves combustible. A fire with a deep bed of coal on top 
of it is maintained in the producer and a mixture of air and 
steam is blown through the fire, thus forming producer gas. 
Water gas is made by blowing steam over or through a hot fire 
of anthracite coal or coke. The passage of steam through the 
fire and the formation of water gas gradually cools the fire so 
that after a time steam must be shut off until the fire can be 
brought back to its former high temperature. In order that 
gas may be supplied continuously, water-gas machines are 
usually worked in pairs. While gas is being made in one 
machine, the fire in the other is being brought to a suitable 
condition for the manufacture of gas and the two machines thus 
make gas alternately. 

33. Oil. —Crude oil is a mineral oil, obtained, like natural 
gas, from wells in certain localities. Crude oil from one oil 
field is not necessarily of the same composition as the oil from 
some other field. Some crude oils are broken up by distillation 
with heat into various lighter oils such as naphtha, gasoline, and 
kerosene, while other oils yield but little of these lighter oils 
on heating. In some cases, it is not economical to distil all of 
the light oils from a crude oil; the residue that is left when dis¬ 
tillation has been carried as far as is economical is used as fuel 
and is called fuel oil. Crude oil from some fields is burned in 
the crude state without the removal of any of the lighter oils. 

34. Powdered Coal. —Bituminous coal is sometimes 
powdered and blown into the furnace when it is burned in a 
manner similar to gas and oil. The coal is powdered to make 


22 


BLACKSMITH-SHOP EQUIPMENT 


48 


possible the efficient use of the fuel and the easy control of the 
fire. When selecting coal that is to be powdered, the same high 
quality of fuel must be chosen as would be used when unpow¬ 
dered coal is burned. Although there are instances in which 
undried coal has been successfully powdered, authorities agree 
that it is generally more economical to dry coal before powder¬ 
ing, than to try powdering the undried coal. The extent to 
which drying should be carried seems, however, to depend on 
the coal and conditions surrounding the individual plant. It 
should, as a rule, be dried until it contains less than 1 per cent, 
of moisture. Coal is dried in a drier that is heated to a moderate 
temperature by a slow fire or by steam. The temperature of 
the drier should never be high enough to drive off the volatile 
matter in the coal. The length of time that the coal is in the 
drier governs the extent to which the water is removed. Most 
driers are arranged so £hat the coal passes continuously through 
them; the moist coal enters at one end and is moved along by 
rotary motion of the drier until it leaves the other end, dried. 
In such a machine, the length of time that the coal is in the 
drier is determined by the speed of the machine. 

35. After the coal has been dried, it is pulverized. The 
fineness to which coal should be pulverized is stated in so many 
ways that it is difficult to find to what extent there is agreement 
or disagreement. The following is, however, about the coarsest 
grinding that has been found to give satisfactory results. All 
of the coal should pass through a screen having 60 meshes to 
the inch, or 3,600 meshes to the square inch, and not less than 
96.8 per cent, should be passed by a screen having 80 meshes to 
the inch. A screen having 100 meshes to the inch should pass 
not less than 94 per cent, and one having 200 meshes to the inch 
should pass at least 34.8 per cent, but not more than 44 per cent. 

The pressure of air that is needed to blow the coal into the 
furnace depends on the size of the furnace and the character¬ 
istics of the coal. When a high air pressure is used, the coal 
travels farther in the furnace before it is burned than when a 
low air pressure is used. The high air pressure is therefore said 
to give a long flame and a low air pressure a short flame. If 


§48 


BLACKSMITH-SHOP EQUIPMENT 


23 


the air pressure is so high that the particles of coal strike the 
side of the furnace before they are burned, the lining will be 
rapidly worn away and the coal will not be burned economically. 

36. A mixture of coal dust and air is explosive and the 
system of pipes and tanks for transmitting and storing powdered 
coal must therefore be tight; and as a further precaution, the 
buildings in which powdered coal is stored or used should be 
thoroughly ventilated. The risk attendant on the use of 
powdered coal, when these precautions are observed, is said to 
be no greater than with other fuels. 

Bituminous coal will sometimes generate sufficient heat, 
when stored in deep piles, to set fire to itself. Fire from this 
cause starts at the bottom of a bin of powdered coal and it is 
unwise to try extinguishing it with water. Water put in at the 
top does not penetrate very far into the pile but forms a blanket 
over it. This soon smothers the fire but spoils the coal. A 
better way to fight the fire is to stop drawing coal from the bin 
or feeding coal to it and to close the bin tightly. The fire will 
then smother itself and only the coal that is burned will be lost. 
Owing to this tendency of powdered coal to heat, it is not safe 
to store it for more than a week or two, and storage bins are 
usually made only large enough to hold a supply of powdered 
coal sufficient to last the furnaces about a day. 


FIRE AND FIRE-TOOLS 

37. The Fire. —In the combustion of fuel, the oxygen 
of the air combines chemically with the carbon of the fuel. 
This chemical combination produces heat; the temperature 
attained depends on the rapidity with which the combination 
takes place, and the amount of heat depends on the amount of 
carbon and oxygen combined within a given period of time. 
Under ordinary conditions, the combustion would not go on 
rapidly enough to generate sufficient heat to raise iron or steel 
to the temperature necessary for working it under the hammer. 
Hence, the draft must be increased in order to supply more 
oxygen to the fuel, and thus increase the rate of combustion. 



24 


BLACKSMITH-SHOP EQUIPMENT 


4 Q 


o 


It is possible, however, to supply too much air and blow the 
fire out, because too much cold air will chill the fire below 
the temperature at which the oxygen will combine with the 
carbon; or it may only lower the temperature by using the 
heat of the fire to warm the excess of air that passes through it. 
The greatest objection, however, to an excess of air is that too 
much oxygen will be supplied to the fire, and some of it will 
combine with the hot iron, forming oxide of iron, which is 
the black scale that falls from heated iron while being forged. 
A fire supplied with an excess of air is called an oxidizing 1 fire, 
but if all the oxygen is used in the combustion and there is an 
excess of carbon, the fire tends to take oxygen from the metal 
that is being heated and it is therefore called a reducing fire. 

A neutral flame neither 
oxidizes nor reduces 
themetal being heated. 

38. A good way to 
start the fire is to heap 
coal all around the 
tuyere to a depth of 2 
or 3 inches, leaving 
the tuyere uncovered. 
A handful of shavings 
or some oil waste is set on fire and put into the opening over 
the tuyere, and a small quantity of fuel is spread over it. 
The blast is turned on very lightly, and as the fire burns up, 
more fuel is added, and the blast is increased. A conical block 
of wood is sometimes used. The block is put over the tuyere 
with the small end down, and the coal packed about it. The 
block is then taken out and shavings put into its place, and 
the fire started. 

39. If coal is used for fuel, it is well to coke a quantity of it 
before putting the iron into the fire. The fire is kept from 
spreading by sprinkling water around the edges. The fire 
should not be allowed to burn too low, because this makes 
it necessary to place the iron nearer the tuyere and brings the 
hot iron too near the cold blast For this reason the blast 



Fig. 17 
















§48 


BLACKSMITH-SHOP EQUIPMENT 


25 


must always have a good bed of fire to pass through before 
coming in contact with the iron that is being heated. The 
hot iron should not come in contact with the fresh coal. As 
the fuel is burned, the coke is brought toward the center and 
fresh fuel is added on the outside of the heap, where it can 
coke slowly. The fire must always be kept clean, all cinders, 
ashes, and scraps of iron being removed. Care should be taken 
to prevent lead and Babbitt metal from getting into the fire, 
as they are objectionable, particularly if welding is to be done. 

If the fire is not to be used for some time, it may be held 
by putting a stick of hardwood into the fire and pounding the 
fuel down around it. The blast is then turned on gently for 




(d) 

Fig. 18 

a few moments to liven it up well. After this, it may be 
left without a blast for an hour or more, and can be restarted 
by turning on the blast. The ashes and cinders are then 
raked out and blown out with the blast, or dropped through 
the tuyere into the cinder pit. 

40. Forms of Fire. —The fire may be maintained either 
open or hollow. In the open fire, the combustion takes 
place on top of the heap over the tuyere; while in the hollow 
fire, a section of which is shown in Fig. 17, the combustion 
takes place at a, the top being roofed over with coke and coal. 
A hole b is left in front for the iron. The advantages of the 
hollow fire are that it is much hotter than the open fire, as the 




1 L T 352B—3 







































26 


BLACKSMITH-SHOP EQUIPMENT 


48 


hot roof radiates heat as well as the hot sides and bottom, and 
it also heats the iron more evenly, and thus lessens the chilling 
by contact with the outside air. 

41. Fire-Tools. —The following fire-tools should be pro¬ 
vided for each forge: A poker, Fig. 18 (a), which is a rod 
of iron or steel about J inch in diameter and at least 20 inches 
long, with a handle at one end; a fire-hook, view ( b ), which 
is similar to the poker, but has a hook bent on one end; a 
shovel, view (c), which has a sheet-iron blade and a long 
handle; and a sprinkler, view ( d ), which consists of a forked 
iron handle sprung into holes in a tin can, the bottom of which 
has holes punched in it for the escape of the water. This is 
used for cooling parts or pieces of iron and for keeping the 
fire from spreading. 


BLACKSMITHING TOOLS 


THE ANVIL 

42. Construction of Anvil. —The ordinary blacksmith’s 
anvil is shown in Fig. 19. It has a horn a on one end, around 
which bending is done. The body of the anvil may be made 
either of wrought iron, or of a special quality of cast iron, or it 
may be a steel casting. The top is faced with steel, which is 
sometimes planed true and then hardened, or first brought 
approximately to shape and then hardened and finished by 
grinding. Anvils having cast-iron bodies usually have unhar¬ 
dened steel horns, which are tough and not easily broken. 
Anvils having wrought-iron bodies usually have horns of the 
same material. It is claimed that the cast-iron body gives 
a firmer backing for the steel face of the anvil than does wrought 
iron. The face of steel is usually hardened under a flow of 
water. If too soft, it will nick; and if too hard, it is liable to 
chip at the comers and edges. Anvils made of cast iron are 
usually brittle. A cast-iron anvil with a horn of the same 
material cannot be used for heavy work because the horn is 




48 


BLACKSMITH-SHOP EQUIPMENT 


27 


liable to be broken off, which is not the case with the wrought- 
iron anvil. For light work, however, the cast-iron anvil will 
give good service. Square-faced anvils without horns are 
frequently made of cast iron, but the edges chip off easily. 


43. The face of the anvil is straight lengthwise, as shown 
from b to c, Fig. 19, but it is slightly crowned crosswise from b 
to d, as shown somewhat exaggerated. If the face of the anvil 
w r ere perfectly flat, a straight piece of iron would show a ten¬ 
dency to curl upwards while being hammered when held cross¬ 
wise of the anvil, and unless it were held perfectly flat on the 
anvil would sting the hand; besides, there would be danger of 
nicking the iron where 
it rests on the comer b m 

of the anvil. When 
hammering a piece of 
iron on the crowned 
face of an anvil, the 
effect of the blow is 
more nearly confined 
to that part of the 
face where the ham¬ 
mer strikes; thus the 
crowned face acts to 
some extent like a bot¬ 
tom fuller. A por¬ 
tion of the edge of the 
face is sometimes rounded, as shown at d. At the right-hand 
end of the anvil there is a square hole e called the liardie liole, 
in which cutting and forming tools are held. The small round 
hole / near it is called the pritchel hole ; the core of small 
holes is punched out through it. 



Fig. 19 


44. Setting an Anvil. —The anvil should be placed on 
a solid block of wood, preferably a butt end of oak, and should 
be fastened to it with iron straps, as shown in Fig. 19, or with 
staples. Anvils on which soft metals are to be worked often 
have a layer of leather, felt, or cloth beneath them. The 

205—3 




































































38 


BLACKSMITH-SHOP EQUIPMENT 


48 


height of an anvil should be such that when the workman 
stands beside it his knuckles will just reach its face. 

45. Weight of Anvil. —The weight of anvils varies 
greatly; small ones are used for light work and large ones for 
heavy work. An average anvil will weigh from 150 to 
200 pounds. Formerly, most of the anvils used in the United 
States were imported from England. These generally have 
the weight stamped on the side, and on many anvils it is given 
in hundredweights of 112 pounds each. If a person stands 
facing the anvil, with the horn to the right, the weight is gener¬ 
ally found stamped on the near side; the figures toward the left 
designate the number of hundredweights of 112 pounds; the 
center figures denote the quarters of a hundredweight; and the 
figures at the right side show the number of extra pounds. 
Thus, if an anvil is stamped 2-2-17, it means 2 hundredweight 
of 112 pounds each, which is 224 pounds, 2 quarters of a hundred¬ 
weight, which is 56 pounds, and 17 pounds, making the total 
weight of the anvil 224 + 56+17 = 297 pounds. However, the 
present practice among American makers is to stamp their 
anvils with the direct weight in pounds. 


HAND TOOLS 


HAMMERS AND SLEDGES 

46. Classification.—Hammers are classified, according 
to weight, as hand hammers , hand sledges , and swing sledges; 




according to the peen, into ball-peen, shown in Fig. 20 (a), cross- 
peen, shown in (5), and long-peen, or straight-peen , shown in (c), 
















§48 


BLACKSMITH-SHOP EQUIPMENT 


29 


47. Hand Hammers. —The hand hammer is made to be 
used with one hand and is handled by the smith himself. It 
should not weigh more than 2\ pounds, a 1-pound hammer 
being a very convenient size for small work. The handle 
should be well formed, elliptic or oval in section, and a little 
thinner toward the head, as shown at a, Fig. 20 (a); this is 
done to give it spring, in order to avoid stinging the hand. 
It is from 14 to 16 inches long, and is made of a size that will 
fit the hand comfortably. A handle of improper shape is apt 
to tire or cramp the hand. It should be durable, not a make¬ 
shift, for the smith soon becomes accustomed to a hammer, 
and knows what effect a blow will have. It is dangerous to use 
a hammer with a loose head. 

48. Hand Sledge. —A hand sledge, 
shown in Fig. 21, is larger than the hand 
hammer. It weighs from 5 to 8 pounds 
and is used by the helper, who holds it 
with both hands. The handle is from 26 
to 34 inches long, and not so slender, in 
proportion, as the handle of the hand ham¬ 
mer. In striking with the hand sledge, the 
helper holds it in both hands and strikes a 
shoulder blow; that is, he raises the head of the sledge to the 
shoulder and strikes from this position. Both large hammers 
and hand sledges are frequently called flogging hammers. 

49. Swing Sledge. —The swing sledge, one form of which 
is shown in Fig. 22, weighs from 8 to 20 pounds, or more. The 
handle is about 3 feet long. In using the swing sledge, the 
helper grasps the handle near the end with both hands, and 
strikes heavily with a full-arm swing blow. The swing sledge 
is also made of the form shown in Fig. 21. 

50. Ball-Peen Hammer. —The ball-peen, or chipping 
hammer, shown in Fig. 20 (a), is a hand hammer that has 
the peen in the shape of a ball. The peen is used in riveting, 
or where it is required to stretch the metal in length and width, 
or for working in a hollow. 
















30 


BLACKSMITH-SHOP EQUIPMENT 


4S 


51. Cross-Peen Hammer.— The cross-peen hammer, 
shown in Fig. 20 ( b ), is used when it is required to stretch 
the metal lengthwise, but not crosswise. The cross-peen hand 


hammer is also used for riveting. 



52. Long- or Straight-Peen Hammer. 

The long-peen or straight-peen hammer, shown 
in Fig. 20 (c), is used when the metal is to be 
spread sidewise. This hammer is made of 
different weights, and is selected to suit the 
work and the strength of the smith; a good set 
of hand hammers consists of a 1-pound ball- 
peen, a Impound straight-peen, and a 2-pound 
cross-peen hammer. 

53. Material Used for Hammers. —Ham¬ 
mers were formerly made of wrought iron or mild 
steel and faced with tool steel. If the whole 
head is made of tool steel, it is liable to chip 
and crack, but with a soft backing this is avoided 
to a great extent. Hammers made of crucible 
steel, commonly called cast steel, that is especially 
suited to hammers are much used and give 
satisfactory service. 

54. Hammer Handles. —Hammer handles 
should be made of the best quality of white, 
straight-grained, second-growth hickory that has 
been well seasoned. The handle should be care¬ 
fully fitted to the eye in the hammer head so 
that it fills the eye as nearly as possible. The 
handle must also be at right angles to the ham¬ 
mer head, so that when striking a blow 



the head will fall squarely, and not on 


the edge. 


FlG - 22 55. The eye in the hammer head is 

generally made larger at its ends than at the middle. When 
the end of the handle is properly wedged, it will spread in the 
eye and hold the handle securely in the head. The eye is 











48 


BLACKSMITH-SHOP EQUIPMENT 


31 


widened sidewise, or lengthwise, and often in both directions 
from the middle of the head toward the outside. If the widen¬ 
ing is sidewise only, but one wedge is used, as shown at a, 
Fig. 23 (a). If widened at the top and bottom, and not at the 
sides, two wedges are driven crosswise as shown at a in (6). If 
the widening is in both directions, three iron wedges are used, 
as shown in ( c ), or three wooden wedges, as shown in (d ). The 
wedges may be made 


either of iron or of 
wood. When wedges 
made of wood are used, 
they should be made 
of dry pine. 








\ 


FORMING AND CUT¬ 
TING TOOLS 

56. Set Ham¬ 
mers.—When a piece 
of work is of such 
shape that it cannot 
be reached so as to 
do the work properly 
with a hammer, a set 
hammer is used. The 
face of the set hammer 
is placed on the part 
of the work where the 
blow is desired, and the 
other end receives the 
blow of the hammer 
or sledge. Sometimes a set hammer is used to prevent marring 
the work, or to give some part of the work a definite form 
not readily obtained with the hammer. The faces of set ham¬ 
mers are formed into special shapes to suit the requirements 
of the various classes of work. The square set hammer shown 
in Fig. 24 (a) is used to produce a flat surface, or make a square 
shoulder or offset. 


(c) 


(d) 

Fig. 23 

























































32 


BLACKSMITH-SHOP EQUIPMENT 


48 


57. Flatter. —The flatter, shown in Fig. 24 (6), is used 
for the same class of work as the square set hammer, the dis¬ 
tinction between the two being that the flatter has a larger face. 




For this reason, it is used to flatten down a surface in finishing, 
while the square set hammer is preferable when a square 
shoulder is to be made and the iron well driven down. 


58. Fuller. —The fuller, shown in Fig. 25 (a), is used in 
spreading the iron. Owing to its shape it concentrates the force 



(a) 




of the sledge blow on a small surface and therefore makes it 
more effective at that place. The fuller spreads the iron at 
right angles to the work edges. Its action is the same as that 






































48 


BLACKSMITH-SHOP EQUIPMENT 


33 


of the cross-peen or long-peen hammer. It is also used for 
hollowing out work. 

59. Swage. —One form of swage, also called a collar 
tool, is shown in Fig. 25 ( b ). Swages are often used in pairs, 
with the lower half, called the bottom swage, placed on the 
anvil with its square shank in the hardie hole. 

The swage is usually a grooved tool, and is used principally 
for forming and shaping bar iron or rods into circular or hexa¬ 
gonal sections. It is also used for forming flanges or collars on 
rods. Each swage is made for a section of a certain size. An 
assortment of four or more 
swages is generally kept at hand, 
hexagonal swages being used on 
bolt heads having six sides. 

60. Punches. —A square 
punch is shown in Fig. 25 (c) 
and a round punch in (d). The 
punch is tapered, being small at 
the point and increasing in size 
toward the handle. The hole is 
made by driving the punch into 
the iron, and is then stretched 
by driving the punch through the work until the desired size is 
obtained. 

61. Cutters. —A cold cutter, to be used with a wooden 
handle, is shown in Fig. 26 (a), and a hot cutter in (6). The 
cutting edge of the cold cutter is slightly convex, and is ground 
so that it is more blunt than the edge of the hot cutter. The 
hot cutter is drawn out thinner than the cold cutter, and its 
edge is sharper. It is used for cutting hot metal. When 
properly tempered and ground, the cold cutter should hold its 
edge when cutting cold iron or steel. When used for this 
purpose, it is frequently called a flogging chisel. The cold 
cutter cuts, or nicks, and at the same time wedges the edges of 
the cut apart, while the hot cutter makes the cut as narrow as 
possible so as not to batter the cut ends. The cold cutter is 
















34 


BLACKSMITH-SHOP EQUIPMENT 


48 


used to nick the metal all around so that it can be broken. 
The cutting edge should be lubricated frequently by pressing 

it into a piece of oiled 
waste or by dipping it 
into water. 




62. For cutting off 
rivet heads, a cold cutter, 
similar to the chisel shown 
in Fig. 26 (a), is used. 
The end of the cutter is formed with a longer bevel on one side 
than the other so that it will not cut the plate from which the 
rivet is being taken. For cutting down a straight surface, the 
side cutter shown in Fig. 26 ( c ) is frequently used. These side 
cutters are made either right or left. 


63. Anvil Tools. —There are a number of tools, made to 
fit into the hardie hole, that correspond in shape to the set 
hammers. The results obtained with them are similar to the 
results obtained with the corresponding set hammers. Fig. 27 
(a) shows a bottom fuller, which, like the top fuller, is 
intended to spread or stretch the iron. The shank of the 
fuller fits into the hardie hole of the anvil. 

A bottom swage with a single groove is shown in ( b ). It is 
similar to the top swage, and they are ordinarily used 
together. Bottom swages are frequently made with two 
or three grooves of different sizes in the same block. 

The hot hardie is shown in (c) and the cold hardie 
in ( d ). They correspond in shape to the hot and cold 
cutters. The hot hardie, being slender and ground to a 
thin edge, is suitable for making a sharp, clean cut; the 
cold hardie is thicker and its edge is ground more blunt, 
so that it may have proper strength to cut cold iron or 
steel. 

The heading tool, shown in Fig. 28, is used in forming 
heads on the ends of rods, bars, bolts, and similar work. FlG - 28 
The hole through the head is usually circular or square. There 
should be an assortment of these heading tools on hand to fit 





















§48 


BLACKSMITH-SHOP EQUIPMENT 


35 


the various sizes of iron bars. The hole should be larger than 
the iron by -^2 inch in the case of §-inch diameter, increasing 
to ys inch on If-inch and larger diameters. 


TONGS 

64. Tongs of various forms are used for handling pieces 
of hot iron. A few of the most common kinds are mentioned 
below. Special tongs are made to fit special forms, and it is 
frequently necessary to make a new pair or to alter a pair to 
fit some oddly shaped piece of iron. The parts of the tongs, 
Fig. 29 (a), are the jaws a 
and the handles b, some¬ 
times called the reins. An 
oval ring a, shown in (d) y 
called the coupler , is fre- 
" quently slipped over the 
handles to hold the work 
tight, and thus relieve the 
hand from the more severe 
part of the holding strain. 

The tongs should always 
be hung on a rack placed 
near at hand to prevent 
their being mislaid. The 
jaws should not be left in 
the fire if it can be avoided, for when they become hot they 
will bend apart and must be bent back before they can be 
used again, and besides they must be dipped into water. 
Repeated heating and dipping makes the iron brittle and 
spoils it. 

Fig. 29 (a) shows a pair of flat tongs used for holding flat 
iron. When closed tightly, the jaws should always be parallel 
and have full-face bearing on the piece of iron being held. 

In ( b ) is shown a pair of pick-up tongs used for picking 
up pieces of iron, also for holding small pieces while tempering, 
etc. The jaws are bent to give them spring and the front bend 
is convenient for holding round iron. 



































36 


BLACKSMITH-SHOP EQUIPMENT 


48 


In (c) is shown a pair of bolt tongs. They are made for 
holding round iron and have a pocket a for the head of the bolt. 



The gad tongs, shown in ( d ), are used for holding flat or 
wedge-shaped pieces that have a head or large end. 

Fig. 30 illustrates a form of tongs that has the lower jaw 
divided into two prongs, while the upper jaw is V-shaped. 
The pressure of the upper jaw on the work being held comes 
between the prongs of the lower jaw. These tongs will hold 
round, octagon, square, and flat pieces of work with a firm 
grip when tongs of the proper size are used. 


BENCH AND FLOOR TOOLS 


65. Swage Blocks.—Figs. 31 and 32 show two forms 
of cast-iron swage blocks. The blocks have variously shaped 
grooves and holes cut in them, and are used like a swage or as 
a heading tool, and for similar work. They are really simple 
forms of dies. Fig. 32 shows a swage block on a stand. The 
grooves h in the edges are used for forming hexagonal heads 

and nuts of various sizes. The block may be 
turned on the stand to bring any side or edge 
up. 



66. Tapered Mandrel. —For forming 
rings and eyes, the cone, or tapered man¬ 
drel, shown in Fig. 33 (a) and (6), is largely 
Fig. 31 used. It is made of cast iron and is formed 

of either one or two pieces. If it is formed of two pieces, as shown 
in (a), the top piece, shown at the left and called the tip, is made 
with a shank on the bottom, which fits into the bottom piece and 
dowels the two parts together. The body a of the mandrel 

























§48 


BLACKSMITH-SHOP EQUIPMENT 


37 


is given a plain smooth taper, but usually a groove b extends 
the entire length. This groove enables the smith to grasp the 
work with a pair of tongs while it is on the cone; or, in the case 



Fig. 32 Fig. 33 


of a ring attached to a chain, or of an eye on a ring, the link 
or eye enters the groove. Some cones are so tapered that 
the upper end c is little more than 1 inch in diameter; the 
diameter of the lower end ordinarily varies between 8 and 
14 inches. The height ranges between 2\ and 5 feet. When 
the cone is made in two pieces, the shank of the tip may be 
placed in a vise to hold it 
firmly for bending small 
work. 

67 . Surface Plate. 

The ordinary surface 
plate is made of cast 
iron, varying in thickness 
from lj to 4 inches, and 
planed smooth on the 
top. This planed face is 
used for testing work, to see whether it is straight, and to detect 
warp or wind. It is also useful in laying out work. The surface 
plate is generally placed on a small strong bench, as shown in 







































































































































38 


BLACKSMITH-SHOP EQUIPMENT 


48 


Fig. 34, so as to be accessible from all sides. It should be care¬ 
fully leveled and then secured in position; this makes it possible 
to test work on it by means of a level. Large surface plates 



are ribbed on the bottom to make them stiffen Surface plates 
about 4 feet wide and 8 feet long are of convenient size for 
general use, the top being about 2§ inches thick, with two side 
ribs around the bottom and several cross-ribs, making the total 
depth of the plate about 8 inches; these plates are used for 
rocker-shafts, yokes, and similar work. For use in shops where 
locomotive frames are made, plates about 4 or 4| feet wide 
by 20 to 24 feet long are used, made as shown in Fig. 35. The 
sides of these plates are 3 inches thick, and are connected by 
ribs as shown. The plate is planed on both sides, and may be 

turned over occasion¬ 
ally to keep it straight, 
as the hammering it 
gets tends to stretch 
the upper surface and 
make the plate high 
in the middle. 

68. Surface 
Gauge. — A surface 
gauge, shown in 
Fig. 36, is used on the 
surface plate to draw, 
or scribe, lines parallel 
to the surface of the plate, on a piece of work c. The sliding 
collar a can be set at any height on the vertical standard b, 
and the needle d can be clamped in any position on this collar. 



































































48 ' BLACKSMITH-SHOP EQUIPMENT 


39 


69. Bench Vise. —The vise is a tool in which work is held 
securely for bending, twisting, chipping, filing, etc. The black¬ 
smith’s vise shown in Fig. 37 
is called a leg vise. The 
leg rests in a solid block on 
the floor, and the body is 
secured to the bench by bolts 
through the strap 5. The 
vise is made of forged steel 
and has tool-steel jaws. 

The screw has a square 
thread, and should be oiled 
occasionally. The top of 
the vise should be set at 
elbow height; this will be 
found most convenient for 
filing and chipping. 

70. Anvil Vise. —In 

shops where heavy horse¬ 
shoeing is done, a heavy 
6 -inch vise can, with advan 
tage, be bolted to a 10" X10" timber post set in the ground near 
the anvil. The jaws of the vise should be at about the same 
height as the top of the anvil. A vise thus arranged has several 
uses, the principal one being to clamp the hot horseshoe while 
bending the heel calk. 

71. Vise Jaws. —A very necessary addition to the vise 

is a pair of copper vise jaws, 
shown in Fig. 38. These are made 
of sheet copper, from to -^o inch 
thick, formed to fit over and be¬ 
tween the jaws of the vise. They 
protect the work from being bruised, 
as it would be if it were clamped 
between the bare jaws. Besides, 

they protect the jaws of the vise, for it is often necessary to 
clamp hot pieces of iron in the vise. This would draw the 





















































40 


BLACKSMITH-SHOP EQUIPMENT 


48 


temper from the jaws if they came in direct contact with it. 
To make them more efficient for this purpose, pieces of asbestos 

paper are placed over 
the jaws of the vise, 
under the copper jaws. 
This makes the insula¬ 
tion very good, and, be¬ 
sides protecting the 
steel jaws, prevents the 
rapid cooling of hot iron 
by contact with the cold 
vise. Sheet-iron jaws 
are often used for hot 
work. 

72, Calipers.—Cali¬ 
pers are used for measuring diameters, widths, and thicknesses. 
Plain calipers are made of two pieces of steel cut to the required 
shape and put together with a rivet. They are made to work 
rather stiffly, so as to remain wherever set, thus making what 
are commonly called firm-joint calipers. Fig. 39 (a) shows a 
pair of outside calipers, and ( b ) a pair of inside calipers. Fig. 40 




Fig. 40 



Fig. 41 


shows a pair of double-joint calipers, which may be set for two 
sizes, as, for instance, the width and thickness of a forging. 












48 


BLACKSMITH-SHOP EQUIPMENT 


41 


73. Dividers. —The dividers, sho^n in Fig. 41, are used 
for measuring the distance between two points and for describ¬ 



ing circles. The points are clamped by means of a thumb¬ 
screw t , which bears against the wing w, and the finer adjust¬ 
ments are made by means of the thumb nut m. The points are 
held apart by means of the spring s. 


74. Threads and Threading Tools. —Threads that are 
cut by hand are usually either V or U. S. standard threads; 
V threads have sharp points at the top of the thread and the 
bottom of the space but the depth of the U. S. standard thread 
is such that a flat place is left at the top of the thread and the 
bottom of the space. 

Two kinds of threading tools are necessary, one for cutting 
inside and the other for cutting outside threads. Taps are used 
to cut inside threads and dies to cut outside threads. A 
blacksmith’s taper tap is shown in Fig. 42. It is made tapering 
so that the size of the thread may be made to fit the work by 
turning the tap only so far into the hole as may be necessary 


wvvwwwx. 

urn 




Z) 


^—-^^^^/wWV^AAAA^y\/“ 


D 


Tct/oer 










B/ug 


vAAA/VVVWWNAAAAAAVV 


imiiiiMiMiii 


\AAAAAAAAA^A^AAAAAV\r 




Bottom/he? 
Fig. 43 


to give the desired fit. The sizes in which blacksmiths’ taper 
taps are usually made and the number of threads for each size 































































































42 


BLACKSMITH-SHOP EQUIPMENT 


48 


are given in Table I. When more than one number of threads 
is given in the table, taps of the given diameter may be had 
with any of these numbers of threads. Tapping that requires 
better fitting threads than are produced by blacksmiths’ taper 
taps may be done with machinists’ taps. These are usually 
made in sets of three taps each as shown in Fig. 43. The taper 
tap cuts a more or less imperfect thread except when it can be 
driven clear through the work. When the taper tap cannot be 
driven clear through the work, it is followed by the plug tap. 


TABLE I 
STANDARD TAPS 


Diam- 

Number of Threads 
to the Inch 

1 

Diam- 

Number of Threads 
to the Inch 

eter 
of Tap 

Inches 

Blacksmiths’ 
Taper Taps 

Ma¬ 

chin¬ 

ists’ 

Taps 

S.A.E. 

Taps 

1 eter 
of Tap 

Inches 

Blacksmiths’ 
Taper Taps 

Ma¬ 

chin¬ 

ists’ 

Taps 

S.A.E. 

Taps 

3 

16 

20, 24, 26, 32 

32 


11 

16 


11 

16 

1 

4 

l8, 20, 24 

20 

28 

3 

4 

10, 12 

10 

16 

5 

16 

l6, l8, 20 

18 

24 

7 

8 

9, 10 

9 

H 

3 

8 

14, l6, l8 

16 

24 

I 

8 

8 

14 

7 

16 

14, l6, l8 

H 

20 

if 

7, 8 

7 

12 

1 

2 

12, 13, 14, 16 

13 

20 

1! 

7, 8 

7 

12 

9 

16 

12, 14 

12 

18 

if 


6 

12 

5 

8 

IO, II, 12 

11 

18 


6 

6 

12 


This tap is slightly tapering for a short distance at the end but 
is full sized throughout the remainder of its length. When a 
full thread must be cut to the bottom of a hole, the plug tap is 
followed by a bottoming tap. 

75. Blacksmiths’ taper taps are made with V threads and 
machinists’ taps are made with either V or U. S. standard 
threads. A machinists’ tap of any given size may have any of 
several different numbers of threads per inch and Table I gives 
the most common number of U. S. standard threads. The most 































§48 


BLACKSMITH-SHOP EQUIPMENT 


43 


common number of V threads for a tap of any diameter is the 
same as for the U. S. standard form with two exceptions; for 
yq inch diameter, 24 V threads and for § inch 12 are used. 
The Society of Automobile Engineers has adopted a standard 
screw thread for automobile work. This thread was formerly 
known as the A. L. A. M. thread, but it is now designated as 
S. A. E. thread. It has the same form as the U. S. standard 
thread but a larger number of threads to the inch is used in 
each case as shown in Table I. 


TABLE H 
TAP DRIXiLS 



Diameter Tap Drill, Inch 


Diameter Tap Drill, Inch 

Diameter 




Diameter 










of Tap 
Inches 

V 

u. s. 

Stand¬ 

ard 

S.A.E. 

of Tap 
Inches 

V 

u. s. 

Stand¬ 

ard 

S.A.E. 


Thread 

Thread 

Thread 

Thread 

3 

9 

9 


li 

9 

3 7 

B 

1 6 

64 

64 


16 

1 6 

64 

1 

3 

3 

7 

3 

B 

5 

1_3 

4 

16 

16 

32 

4 

8 

64 

5 

1 5 

1 

1 7 

7 

23 

4 7 

B 

16 

64 

4 

64 

8 

32 

64 

3 

19 

5 

21 


5 3 

2 7 

29 

8 

64 

16 

64 

1 

64 

T2 

32 

7 

1 1 

23 

3 

T 1 

59 

61 

T 1 

16 

32 

64 

8 

1 8 

64 

64 

1 64 

1 

1 3 

1 3 

7 

T 1 

t 3 


T 9 

2 

32 

32 

16 

1 4 

1 64 

1 67 

1 64 

9 

16 

29 

64 

2£ 

64 

1 

2 

if 

l i 

T li 

1 64 

T n 

1 64 

5 

8 

1 

2 

JL3 

64 

35 

64 

ij 

iH 

rl9 

1 64 

t 2JL 

1 64 


76. Holes that are to be tapped must be drilled somewhat 
smaller than the size of the tap. Theoretically, the diameter 
of the hole that is to be tapped should be equal to the diameter 
of the tap at the bottom of the thread so as to make a full 
thread in the tapped hole. It is, however, frequently found 
advisable in practice to drill the holes slightly larger than the 
diameter of the tap at the bottom of the thread, even though less 
than a full thread is produced when the hole is tapped. Tap 
drills are used to drill holes for tapping. The diameter of the 
tap drill for any certain size of tap depends somewhat on the 
kind of thread that is to be cut. Table II gives the tap-drill 


205—4 


























44 


BLACKSMITH-SHOP EQUIPMENT 


48 


sizes for the various kinds of threads. These tap drills do not 
leave enough stock in all cases to make a full thread but the 
thread will be full enough for most practical purposes. 



A die with which threads are cut on the outside of the work is 
held in a die-stock. The stock is shown at a, Fig. 44 (a), with 

an opening b to receive the dies c, which 
are held in place by the setscrew, as 
shown. The dies are shown in greater 
detail in view ( b ), the cutting edge 
being at /. The dies may be removed 
from the stock and replaced by others 
so the one stock will serve for several 
different sizes of dies. 


77. Post Drill. —Holes may be 
drilled by means of a post drill, which 
is a machine that is fastened to a post 
or a wall of the building. Such a ma¬ 
chine is shown in Fig. 45. The drill a 
is held in the spindle b and the work 
that is being drilled rests on the table c. 
The spindle is turned by hand or by 
power through gearing d. The fly¬ 
wheel e makes the speed of the drill 
more uniform than could be main¬ 
tained without it. The drill may be 
fed up and down by means of the 
wheel / which may be either turned by hand or by the pawl g 
working in the ratchet on top of the wheel /. The pawl works 


















































































































§48 


BLACKSMITH-SHOP EQUIPMENT 


45 


automatically when the drill is in operation and it will give a 
more uniform feed than can be obtained by hand. The table c 
may be clamped at any height on the column, h. 

78. Marking Materials. —A soapstone pencil is the best 
material for making surface marks on iron, although chalk, 
slate pencils, and crayons are used for the purpose. Soapstone 
marks will not bum off, and the end of the pencil may be 
filed wedge-shaped and used to give a sharp clear line for laying 
out work. Soapstone pencils are made both round and rec¬ 
tangular in section; in either case, the pencil is usually from 5 to 
6 inches long. The round pencils vary from J to § inch in 
diameter; the rectangular ones are usually | inch thick by 
| inch wide. 

79. Scriber. —In some cases, it is desirable to scribe on 
the metal a line that will cut through the surface scale. To 
do this, a steel scriber of the general form shown in Fig. 46 
is used. It is usually from 
3 % to j inch in diameter and 
from 6 to 8 inches long. 

The point must be quite 
hard, and the temper of the rest of the tool must be carefully 
drawn to secure the necessary elasticity and to prevent the point 
from breaking off. 

80. Other Methods of Marking. —White lead, or zinc 
white, mixed in naphtha or boiled linseed oil and applied with 
a slender brush, is often used to letter and number pieces of 
work, especially when shipped to a distance. Before laying 
out, the surface where lines are to be made may be whitened 
by rubbing with lump chalk or by coating with whiting and 
water, turpentine, or wood alcohol, which may be applied 
with a brush, and will dry quickly. When laying out work, 
the hand cold chisel and the center or prick punch are fre¬ 
quently used to locate the ends and intersections of lines 
marked on the piece of iron. Lines are often marked by a 
succession of dots made by the prick punch at intervals of 
from J inch to 2 inches, according to the nature of the work. 





46 


BLACKSMITH-SHOP EQUIPMENT 


48 


81. Cold Chisel. —The cold chisel is usually of the form 



y 


n 


y 


8 inches long, made 
of J-inch octagon 
tool steel, is com¬ 
monly used for gen¬ 
eral purposes. Small 
chisels are made of 
f inch, or smaller, oc¬ 
tagon steel. The il¬ 
lustration shows the 
edges formed by faces 
ground at an angle 
of 60°. 


(C) 


82. Cape Chisel. 
The cape chisel shown in Fig. 47 ( b ) is used for cutting and 
trimming narrow grooves and slots, and is made in widths to 
correspond to the widths of the grooves to be cut. The length 
of the cutting edge should be slightly greater than the width 
of the tool behind it, to give clearance for the cut. 


83. Center, or Prick, Punch. —The center, or prick, 
punch, shown in Fig. 47 ( c ), is made of the same material as 
the cold chisel. The size varies with the nature of the work, 
and may be from about |- to f-inch octagon steel. It is used 
to mark centers of holes to be drilled and to make small dots or 
marks wherever desired. 

84. The Bevel. —A 

common form of bevel 
is shown in Fig. 48. The 
bevel is used to lay off 
angles other than right 
angles, and is usually set 
from a drawing or tern- Fig. 48 

plet, or from a sample. It is sometimes called a T bevel, and often, 
incorrectly, a bevel square. The form illustrated has a cast- 
iron stock a with a slot in the middle of one end, through which 
















































§ 48 BLACKSMITH-SHOP EQUIPMENT 47 

slides a steel blade b, slotted for about one-half its length and 
capable of adjustment about a pivot in the end of the stock. 



Fig. 49 

The adjustment of the blade consists in varying the length 
of the projection of the blade b from either side of the stock, 
and of varying the angle that it makes with the stock. When 
the blade is set as desired, it is clamped by turning the thumb 
nut c on the end of the stock. The side edges of the blade are 
parallel and the solid end d is generally cut at an angle of 45°, 
or one-half a right angle, with the edges. Care must be taken 
not to tighten the thumb nut with more than a gentle pressure, 
otherwise the threads may be stripped from the screw. It is 
well to keep in mind, for use in checking up work, that the 
sum of the two angles formed by an edge of the blade with the 
sides of the stock is equal to two right angles. For testing 
angles while the work is hot, there is usually a shop-made 
bevel formed of two strips of steel, about § or ye inch thick 
by | or j inch wide, and from 12 to 16 inches in length. These 
pieces are riveted together at one end and are made to work 
rather stiffly, so that they will remain wherever set. 

85. Measures.—For measuring long rods, or bars, such 
as suspension rods and hangers, the more careful workmen 
generally use a steel measuring tape. For the general require¬ 
ments of measuring small work, both straight and curved, a 
thin metal rule, 2 feet long by J inch wide, folding in the middle, 
is used. It is made either of a good quality of tempered spring 
steel or of hard-rolled brass. Fig. 49 illustrates the general form 


d 


( 

) 

l 

■ 111111 

> 

rhlili 

3 < 

ililili 

I t 

1111111 

> 6 

111 1 111 i III ill 

7 8 S 

ililililililili 

) 10 1 

tllllllllllllll 

1 1 

lllllll 

U— — 

b 


Fig. 50 


of this rule. The rule shown in Fig. 50 is intended especially 
for use on hot iron. It is made of brass and has a handle a 





































































48 


BLACKSMITH-SHOP EQUIPMENT 


§48 


so that it can be used on hot work and cooled by plunging into 
water without danger of rusting as would be the case if it were 
made of steel. There are graduations on each side of the rule; 
those shown start at the toe b so that measurements may be 
taken from the outside edge of a piece of work. The gradua¬ 
tions on the other side are placed along the edge c d and start 
at the end c so that measurements may be taken from an 
inside corner. 

86. Measuring Wheel, or Circular Rule. —The meas¬ 
uring wheel, or circular rule, shown in Fig. 51, also called a 
traveler , a traverse wheel , or a tire wheel, is usually a thin circular 
ring a about -A inch thick. Sometimes the hub consists of a 
thimble fitted into a hole in the center of the wheel. This 



thimble also forms the support for an index arm, or pointer, b 
which turns with the wheel and may be set to any point on its 
circumference. The spindle c on which the wheel turns is held 
between the ends of a forked handle d, as shown. Sometimes 
a boss is stamped on one side of the wheel to form the hub, 
which is threaded and fitted with a thumb nut to bear on the 
pointer and hold it in position. The measuring wheel is 
sometimes a drop forging turned true on the edge and having the 
division marks stamped on one side in the process of forging. 

87. The wheel usually has a circumference of 24 inches, 
which is subdivided on one side into inches, halves, quarters, 
and eighths, the zero and 24-inch marks being at the same 
















48 


BLACKSMITH-SHOP EQUIPMENT 


49 


point. Sometimes, however, the wheel is plain with the 
exception of one short radial line on one side touching the 
circumference. The wheel is carefully rolled over the length of 
the work to be measured, the measurement being started at, 
and read from, the zero line. The pointer is moved to indicate 
the point on the circumference of the wheel where the measure¬ 
ment ends. The number of complete revolutions of the wheel 
must be counted. Chalk marks on a plain wheel often serve 
as substitutes for a zero line and pointer. On curved work, the 
wheel should be moved over the line of mean length, between 
the outside and inside measurements. 

88. Saws.—The hack saw is now usually considered a 

necessary part of the blacksmith-shop equipment. Hack-saw 
blades vary in length from 
6 to 16 inches, and even 
longer, and may be used 
either in hand frames or < a ) 

in specially designed 
frames moved by power. 

The hand frame illus¬ 
trated in Fig. 52 (a) is 
an adjustable frame, in fig. 52 

which blades from 8 to 12 inches long can be used. The 
clamps holding the blade may be turned so that the blade 
will cut up or down in the plane of the frame, or at right angles 
to the frame. Thus it is seen that the blade may be turned 
to face any one of four ways. The blade is shown in (6) set at 
right angles to the plane of the frame. 

89. Hack-saw blades are so hard that they cannot be filed, 
and are so cheap that when dull they may be thrown away. 
They are made with about 25 teeth to the inch for sawing thin 
metal, and with about 14 teeth for other work. The blades 
used in hand frames are about yffo inch thick and } inch wide, 
an 8-inch or 10-inch blade being the most economical. The 
operator should lift the frame up slightly when drawing the saw 
back, for the back stroke is much more destructive to the teeth 
than the forward stroke 






















50 


BLACKSMITH-SHOP EQUIPMENT 


48 


90. Power Hack Saw. —For cutting off bar stock, a 
power hack saw, like that shown in Fig. 53, will be found exceed¬ 
ingly useful. Such a machine is usually provided with a vise 
for holding the stock to be cut off, and is so constructed that 
the machine will stop when the piece has been sawed through. 
Provision is also made for lifting the saw on its back stroke so 
as to save the teeth. The blades are generally 12 inches or 
more in length, and will cut stock up to 4 inches in diameter. 

91. Rotary Cold Saw. —When it is necessary to cut a 
large number of pieces, the power hack saw will be too slow 



and a rotary cold saw like that shown in Fig. 54 may be used. 
The saw a is carried on a spindle that is driven by gearing 
from the pulley b. The work that is to be cut is held in the 
clamps c and d which may be moved crosswise of the machine 
as required and fastened down by bolts e that reach through 
the clamps into the T slot /. The length of the work may be 
gauged by the stop g. While the work is being cut, the car¬ 
riage h, on which the saw is mounted, is moved forwards by a 
mechanism that is not shown. The carriage movement is driven 






































BLACKSMITH-SHOP EQUIPMENT 


51 


§48 


by the wheel i that takes power from the main drive pulley b. 
The saw may, however, be moved forwards and backwards by 



hand by turning a wheel, not shown, at the left end of the 
machine. 


NOTICE TO TIIE STUDENT 


READ CAREFULLY BEFORE ANSWERING 
EXAMINATION QUESTIONS 

That the student may understand what is expected in answer 
to the Examination Questions at the end of each Section, the 
following examples of questions and answers are given. It will 
be noted that each answer is short, yet it tells all that is asked 
for in the question. 

In answering the Examination Questions, the student should 
read each question carefully to make sure that he understands 
what is required; then he should write an answer that tells clearly 
just what is asked for in the question, using his own words as 










































































52 


BLACKSMITH-SHOP EQUIPMENT 


48 


far as possible. By following this plan, he will obtain the 
greatest benefit from his Course. If the student is unable to 
understand a question, or to answer it after having studied the 
text carefully, he should write to the Schools at once for help. 

Question 1.—How many threads per inch are there on a 1-inch 
blacksmith’s tap? 

Answer.—8. 

Question 2.—At what height should the bench vise be set? 

Answer. —Elbow height. 

Question 3. —What advantages are claimed for powdered 
coal? 

Answer. —The more efficient use of the fuel and easier con¬ 
trol of the fire. 

Question 4. —How many blowers are required for a down- 
draft system? 

Answer. —Two are generally used, but for a small installation 
one can be arranged to do both the blowing and exhausting. 

Question 5.—What protection from the heat is provided for 
the operator of oil- and gas-fired furnaces? 

Answer.—A water-cooled shield is located across the front 
of the furnace. 


HAND FORGING 

(PART 1) 

Serial 1687A - Edition 1 

MANUFACTURE OF IRON 


CAST IRON 

1. Any iron-bearing mineral from which the metal can be 
abstracted at a profit is iron ore. This definition excludes 
many ores containing a large percentage of iron because they 
also contain a large percentage of impurities; and it will admit, 
on the other hand, many ores that carry a low percentage of iron, 
but few or no injurious elements. Iron is never found chemi¬ 
cally pure in nature, except perhaps in some meteorites, where it 
is a mere curiosity, while the limited supply from this source 
makes it of no practical value. Chemically pure iron is soft and 
ductile, has a high melting point, and can be forged and welded. 

The rich ores of iron contain from 60 to 68 per cent, of metal¬ 
lic iron; but those low in iron, called lean ores , may contain 
only from 30 to 40 per cent. In the United States, veiy few 
furnaces are running on ore containing less than 50 per cent, 
of iron. The impurities, which consist of oxygen, silicon, 
phosphorus, lime, sulphur, magnesia, aluminum, manganese, 
titanium, etc., occur in very small amounts. 

2. Blast Furnace. —Iron is reduced from its ores by 
fusing them, together with lime, in a blast furnace ; the lime 
acts as a flux , and is obtained by the use of limestone. A blast 
furnace is usually an iron shell lined with some refractory 
substance, such as firebrick or fireclay, and on the outside looks 
like a tall stack or chimney. Into it alternate layers of fuel, 

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fiux, and iron ore are thrown, the fuel fired, and the whole mass 
raised to a high temperature by means of a hot-air blast, to 
hasten the combustion. The blast furnace is continuous in its 
operation; the ore, flux, and fuel are charged into the top of the 
furnace, and the metal and flux melted by the intense heat are 
tapped out at the bottom. The amounts of fuel, limestone, 
and ore must be carefully calculated in order that the ore may 
be properly reduced. The furnace is so operated that the 
impurities in the fuel and ore may combine with the flux in the 
form of slag, which is lighter than the molten iron and floats 
on its surface. The slag is tapped from a hole at the side of 
the furnace, above the hearth, or bottom, while the iron is 
tapped from a hole at the front and bottom of the furnace and 
flows into iron or sand molds,where it cools. The form of cast 
iron so obtained is called pig iron. 

3. Nature and Composition of Cast Iron. —The best 
and purest grades of cast iron are made in blast furnaces that 
use charcoal for fuel, because charcoal does not contain sulphur, 
while coal and coke do; and also because the ash is of such a 
nature that the impurities pass into the slag rather than into 
the iron. Cast iron, as made by blast furnaces, generally 
contains from 92 to 96 per cent, of metallic iron. The other 
4 to 8 per cent, consists chiefly of impurities in the form of car¬ 
bon, silicon, manganese, phosphorus, and sulphur, from 2 to 
6 per cent, being carbon. While it is true that the five ele¬ 
ments mentioned are impurities in iron, the first four fire really 
the elements that make cast iron of commercial value. Cast 
iron has a granular or crystalline structure, and is hard and 
brittle. It can be cast in almost any desired shape, but can¬ 
not be forged or drawn into wire. 


WROUGHT IRON 

4. Wrought iron has a fibrous structure and can be forged 
and welded. It is made from pig iron, and while it has been 
practically freed, by the puddling process, from carbon, silicon, 
and the other elements contained in cast iron, small amounts 
remain, their complete removal being too costly. 



§49 


HAND FORGING 


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5. Hand Puddling.— In the manufacture of wrought 
iron by hand puddling, the pig iron obtained from the blast 
furnace is melted on the hearth of an open-lieartli furnace 
which is ordinarily of the form shown in-Fig. 1. The hearth a 
is usually made of cast-iron plates carried on brick walls or 
on iron supports b. It is generally about 5 or 6 feet in length 
and 4 feet in width opposite the charging door, and is lined with 
a refractory substance. The roof is a firebrick arch. The 
heat is obtained ordinarily from a bituminous-coal fire in the 
fireplace c. The area of the grate varies from 6 to 10 square 
feet or more, depending on the character of the iron, the draft, 



Fig. 1 


and the fuel. Between the grate and the hearth is a firebrick 
wall d, called a bridge wall , that extends across the furnace and 
is of sufficient height to keep the fuel from getting over on the 
hearth, and the molten iron from running over on the fuel. 
In many cases, the bottom and sides of the furnace are hollow, 
and water is circulated through them to keep them cool. 
Another bridge wall e, called the altar, prevents the metal from 
overflowing into the flue leading to the chimney /. In the middle 
of the door g in the side of the hearth is an opening large enough 
to admit the puddler’s rabble; this is a long iron bar with which 
the melting charge of metal and slag is stirred by the workman. 
































































































































































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6. The furnace is charged with 500 pounds of pig iron, 
which is carefully placed on the bed of the furnace or is broken 
up and piled around the sides. When the charge is melted, 
the puddler stirs the fluid mass with his rabble, while his assis¬ 
tant changes the draft and the fire to suit the different stages 
of the process. The impurities of the iron are taken up by the 
molten flux or are burned out. In about an hour, pasty masses 
of metal begin to appear, which the puddler works into spongy 
balls weighing from 60 to 80 pounds each. These balls are 
well worked at a high temperature to get rid of the slag, and 
finally removed from the furnace and hammered or squeezed 
into the form called a bloom. The bloom is then taken to the 
rolling mill, and rolled into various commercial forms. 

7. Mechanical Puddling. —In the various puddling 
machines in use, the flame is led from the firebox to a hearth 
of varying form and construction, moved by machinery. In 
some forms this hearth is barrel-shaped and turns on a hori¬ 
zontal axis. In other forms it is circular, and is so arranged 
that it may be mounted on a vertical shaft and rotated; but 
in one form the hearth slants at an angle of from 10° to 15° 
from the horizontal. In most cases the metal is further stirred 
or mixed by broad-bladed rabbles operated by the workmen 
or by machinery. 

The advantages claimed for these machines are that greater 
masses of metal may be handled and that there is greater uni¬ 
formity of the product, together with a saving of fuel, time, 
and expense. Hand puddling is also injurious to the health 
of the workmen. 

8. Bundled Scrap. —A good deal of wrought iron is made 
from wrought-iron scrap, which is bound together by wire 
into bundles of convenient size and heated in a furnace. When 
the iron has been brought to a welding temperature, the 
bundles are removed and rolled into bars. The wrought iron 
thus made, however, is usually of poorer quality than that pro¬ 
duced by the puddling process, probably because the scrap is 
apt to contain some steel. 


49 


HAND FORGING 


5 


9. Effect of Reheating Wrought Iron. —Experiment 
has proved that the strength of wrought iron is increased by 
repeated heating and rolling until about the sixth working. 
Beyond this point, each reworking decreases the strength, 
until, at about the twelfth, the iron will have no greater strength 
than after the first rolling. Careless heating may injure the 
iron and weaken it in one or two heats. 


LOW-CARBON STEEL 

10. Properties of Low-Carbon Steel. —The difference 
in the manufacture of wrought iron and low-carbon steel lies 
in the fact that wrought iron is produced by puddling a pasty 
mass of pig iron, squeezing out the slag, and rolling the iron 
into a bar, whereas low-carbon steel is produced by melting 
iron, pouring it into ingots, and rolling these ingots into rods 
and bars. The amount of carbon in low-carbon steel is gen¬ 
erally from .1 to .5 per cent., although it may be as high as 
.75 per cent. Carbon gives strength and hardness, but makes 
the material less ductile and malleable. Low-carbon steel is 
used for forge work, bridge building, ship building, railroad 
work, and many other purposes. A grade of low-carbon steel 
particularly suitable for forgings contains about .1 per cent, 
of carbon, and is known as mild steel , or machinery steel. It is 
stronger than wrought iron and can be used for almost every 
class of work for which wrought iron is used. 

11. Manufacture of Low-Carbon Steel. —Low-carbon 
steel may be made by the crucible process , the Bessemer process , 
or the open-hearth process. The process used will, to a large 
extent, determine the percentage of impurities it contains, and 
generally the presence or absence of other elements than car¬ 
bon determines the fitness of any given steel for different classes 
of work. 

12. The crucible process is used most largely for the 
manufacture of alloy steel and tool steel, but also some low- 
carbon steel is made by that process. Briefly, the process con¬ 
sists in charging a number of covered crucibles with pieces of 



6 


HAND FORGING 


§49 


wrought iron, on top of which the desired amount of carbon 
is placed. The iron in the crucibles is melted and absorbs the 
carbon, thus producing steel with any desired percentage of 
carbon. 

13. In the Bessemer process, molten iron containing a 
considerable amount of carbon and silicon is placed in a con¬ 
verter ; this is a pear-shaped vessel with an opening in the top 



Fig. 2 


at a, Fig. 2, and supported on trunnions b, b' so that it can be 
rotated. The converter is partly turned on its side and the 
charge of molten iron poured into it; compressed air is then 
admitted through the trunnion b, which acts as a valve, as the 
converter swings to its upright position. This air passes 
through the pipe c to the bottom d of the converter and up 
through the holes e in the lining. It rushes through the molten 






























































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HAND FORGING 


7 


metal and bums out the carbon and silicon. The air pressure 
must be sufficient to prevent the steel from flowing through 
the openings e into the bottom of the converter. Theoretically, 
the carbon can be burned out to any desired point and the 
operation stopped, thus producing steel containing the desired 
percentage of carbon; but in practice it is found exceedingly 
difficult. Hence, all the carbon is burned out and then th 
desired quantity is added by putting in an iron high in carbon. 

14. In the Bessemer process, silicon, which is one of the 
acid elements, is burned out; hence, this process, known as 
the acid Bessemer process , is generally used, especially in the 
northern and central portions of the United States, where most 
of the pig iron is free from phosphorus and high in silicon. 
The pig iron from which steel is made by the acid Bessemer 
process must be low in phosphorus, which cannot be burned 
out by this method. 

Bessemer steel is also made by what is known as the basic 
Bessemer process. In it silicon cannot be burned out to any 
great extent, and hence iron low in silicon must be used. It 
may, however, contain a greater percentage of phosphorus, 
as some of this is burned out. The converter must be pro¬ 
vided with different linings for these two processes. As steel 
can be more cheaply made by the Bessemer process than by 
any other, it is used largely for manufacturing steel rails, 
structural shapes, etc.; also, for steel forgings, especially those 
of moderate size. 

15. In the Bessemer process, the steel is made from pig 
iron, but in the open-hearth process a large portion of the 
charge is scrap steel that has already been purified. In the 
Bessemer process, air is blown through the melted iron to bum 
out the carbon, but in the open-hearth process the carbon is 
removed by a flame burning against the surface of the melted 
iron. The open-hearth process, therefore, requires a large 
surface of metal with but little depth and takes its name from 
the style of furnace in which the steel is made. An open- 
hearth furnace is shown in Fig. 3. The iron is heated in the 
hearth, or basin a, and the air and gas enter and the burned 


205—5 


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HAND FORGING 


49 


gases escape alternately through flues b and c. The cham¬ 
bers d , d ', and e , e' are nearly filled with firebrick or thin tile 
checkerwork containing wide open spaces. When the process 
is completed, the metal is drawn from the hearth through a 
spout at /. In some furnaces of recent design, the hearth a 
can be tilted toward the spout to pour the steel, the ends being 
stationary, as in the furnace shown. 

16. The furnace is sometimes started by melting pig iron 
on the hearth and sometimes by using melted iron just as it 
comes from the blast furnace. Air is admitted through the 
checkerwork e , Fig. 3, gas is admitted through the checker- 
work e', and the air and gas mix and burn at b. The flame 



Fig. 3 


is directed downwards so that it strikes the surface of the 
metal in the hearth, causing it to be heated to a very high tem¬ 
perature. The burned gas passes out at c, through the cham¬ 
bers d, d’, heating them as it passes to the chimney. When 
the checkerwork in d, d' is heated sufficiently, valves that con¬ 
trol the direction of flow of the air and gas are changed so that 
the air enters through d and the gas through d\ and the burned 
gases pass out at 6, heating e and e'. By thus reversing the 
direction of flow of the air and gas about every 20 minutes, 
the checkerwork can be heated to a very high temperature. 
The heat taken up by the checkerwork is then given up to the 
entering air and gas when the direction is reversed. Because 


















































































































































































§49 


HAND FORGING 


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of this heat, the temperature of the flame is greatly increased; 
such a furnace is called a regenerative open-hearth furnace. 

17. During the process, the carbon and impurities on the 
surface are burned out as the molten mass is rabbled , that is, 
worked by using a long bar. The rabbling brings to the sur¬ 
face the metal in the bottom of the bath and aids in producing 
a uniform mixture of desired quality. 

During the Bessemer process, samples of the charge can¬ 
not be taken and tested; but in the open-hearth process, the 
charge is in the furnace for a greater length of time, and sam¬ 
ples are taken from time to time, a quick analysis made, and 
the necessary changes made in the treatment to produce the 
desired quality. In this way, a steel of any desired compo¬ 
sition can be made without adding carbon, which is, at best, 
a somewhat uncertain method. In the open-hearth furnace, 
as in the Bessemer converter, both acid and basic processes 
may be used, depending on the elements burned out. The 
lining must, however, be selected to suit the charging material. 

18. Open-hearth steel is generally of more uniform grade 
and purer than Bessemer steel; but the furnace and regener¬ 
ative stoves are expensive, the time required in the process is 
greater, and the fuel, flux, and other charging materials greatly 
increase the cost of production, so that this class of steel is 
always more expensive than Bessemer steel. Open-hearth 
steel, however, is of better quality and greater strength and is 
used where the requirements are very exacting. By exercising 
great care in the manufacture, a good grade of steel may be 
made by either process; but ordinarily the higher grades are 
made by the open-hearth process. 

19. Defects in Ingots. —The steel as it comes from the 
open-hearth furnace or the Bessemer converter is poured into 
a large ladle and then into iron ingot molds. The surface of 
the metal is, of course, immediately chilled, and solidifies; 
the center, however, and especially the upper part, remains 
molten for some time. As the interior gradually cools, the 
sulphur and other impurities are driven toward the center, 
or to the part that cools last. As the metal also shrinks 


10 


HAND FORGING 


49 


considerably in cooling, a shrink hole of varying size, filled with 
gas, is formed in the top of the ingot, as shown at a, Fig. 4. 
When this shrink hole extends more than half way down the 
ingot, it is known as piping. 

20. The piped ingot, if drawn down into a forging, will have 
a flaw running through its center, of a length corresponding to 
that of the piping in the ingot. As the gas from the interior 
cannot escape except by passing through the solidified surface 
of the metal, the hole in the finished forging will have approxi¬ 
mately the same volume as the pipe in the 
original ingot. For large, high-grade forgings, 
a large ingot should be made and the upper 
portion cut off, as it contains the greater part 
of the impurities and any piping that may 
have taken place. In some ingots this piping 
effect is comparatively small; but for important 
forgings the upper portion of the ingot should 
never be used. 

21. Rolling From Ingot. —As soon as it 
has solidified, the ingot is usually taken from 
the mold and rolled to the desired shape with¬ 
out reheating. The rolls used for this purpose 
are made with a series of grooves. The ingot 
is first passed through the largest groove, then 
back through the next smaller, and so on, the size being 
decreased at each pass until the desired form is obtained. If 
a better product is desired, the rolled bars are cut into small 
pieces, piled in bundles, and reheated to a welding temperature. 
The bundles are then passed through the rolls in the same way 
as the ingots. This rewelding and rolling may be repeated two 
or three times, if desired. The bars thus produced are usually 
a trifle over standard size. 

• 22. Cold-Drawn Steel. —In the manufacture of cold- 
drawn steel rods and bars, the rough-rolled stock is first pickled 
in a weak solution of sulphuric acid to remove the scale, and 
then passed through a lime solution to remove all traces of acid. 
The rough rods and bars are larger than the finished size, and 








§49 


HAND FORGING 


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they are brought to the exact diameter desired by being drawn 
through steel dies. All bars up to inches in diameter are 
reduced Yt inch during the drawing process, but between 
2J and 3 inches the reduction of size is f inch. After being 
drawn, the bars are passed through straightening rolls, by 
which they are straightened and given a surface polish. The 
drawing operation, which is performed on the cold bar, gives 
the bar greater strength and a harder surface and produces 
a finer finish. Cold-drawn steel may be made flat, square, 
or round in section. It is largely used for shafting and is made 
in sizes from J to 6 inches in diameter. The sizes from 3 to 
6 inches in diameter are not cold drawn, but are turned and 
then cold rolled and straightened. 

23. Effect of Sulphur and Phosphorus. —Sulphur in 
iron and steel renders these materials hot short, or brittle when 
hot. Phosphorus, on the other hand, makes them cold short, 
or brittle when cold. Sulphur also decreases the strength 
and ductility of steel. For these reasons, the amount of sul¬ 
phur or phosphorus in forgings should not exceed .1 per cent. 
The grade of iron known as Swedish iron, which is a kind of 
wrought iron imported from Sweden or Norway, is practically 
free from sulphur and phosphorus. It is made from the richest 
ores and is used for special work. As it is very soft, it can 
easily be welded and forged. 

24. Classification of Bar and Band Iron. —The width 
and thickness of cross-section of iron and steel determine 
whether the material is to be classed as bars or bands, rods 
or wire; but there seems to be considerable difference of opinion 
among manufacturers as to the limits of thickness on which 
the classification is based. One method of classification is 
as follows: Flat iron more than ye inch thick and not more 
than 6 inches wide is bar iron; but if it is from ^ to n inch 
thick, and not more than 6 inches wide, it is called band iron. 
Below ^ inch in thickness, it is known as sheet iron or sheet 
steel. Stock more than ^ inch thick and more than 6 inches 
wide is called plate. Rods are bars of circular cross-section not 
less than ye inch in diameter; smaller sizes are classed as wire. 


12 


HAND FORGING 


§49 


FORGING OPERATIONS 


DEFINITIONS 

25. The operation of shaping or forming metal by ham¬ 
mering or pressing is termed forging. 

The process of stretching a piece of metal in one or more 
directions, either by hammering or by pressure, is called draw¬ 
ing. 

By the term bending is usually meant the turning or form¬ 
ing of the iron in such a manner as to deflect it from a straight 
line. The finished product may be a curved or an angular piece. 

In the operation of twisting an iron bar, the fibers are 
wound around each other spirally. No change occurs in the 
direction of the axis of the piece. 

Upsetting is the operation of increasing the thickness of 
a piece of iron by shortening it. 

Shrinking is the operation of fastening a ring or a band on 
a piece, making use of the expansion that takes place when the 
ring is heated to a dull red. When cooling, the band con¬ 
tracts and grips the work tightly, if the proper shrinkage allow¬ 
ance has been made. 

Welding is the process of uniting two pieces of metal into 
one solid piece by heating them to a welding heat and ham¬ 
mering or pressing them together. For wrought iron, a white 
heat is necessary to soften the metal so that it will weld. 


GENERAL DIRECTIONS 

26. Care of Fire. —The results obtained in forging and 
welding depend largely on the condition of the fire in which the 
work is heated. The fire must be kept clean and free from 
cinders or other foreign matter. The air blast should come up 
through the center and should pass through a solid bed of coke. 
The pressure of the blast should not be too great. 




49 


HAND FORGING 


13 


27. Placing Work in Fire. —The work should be placed 
below the top of the fire, so that the oxygen of the surrounding 
air cannot come in contact with it; on the other hand, it must 
not be placed too low in the fire, or the air from the air blast 
will come in contact with it. If the air comes in contact with 
highly heated iron, the oxygen in it will attack the metal, 
forming scale. If cinders and clinker are allowed to accumu¬ 
late they will let the air pass freely up through the fire with¬ 
out burning out the oxygen, and thus are apt to cause the work 
to be injured. To insure even heating, the work should be 
placed horizontally in the fire, with the hottest part of the fire 
surrounding the point that is to be heated. In the case of 
beginners, the work should be placed in such a position that the 
progress of the heating can easily be observed. If the work 
varies in cross-section, the larger part should be heated first, 
and then the smaller, as the larger requires a longer time to 
reach the desired temperature. To insure even heating, the 
work should be turned over in the fire. 

28. Judging Temperature by Color. —The experienced 
workman is able to judge the temperature of a piece of work 
by the color. If a piece of iron is put in the fire and slowly 
heated, its color will change as the temperature increases. 
When it has been heated to such a temperature that it has a 
dull-red color when viewed in a dark place, but is black when 
seen in the light, it is said to be black hot. As the heating 
proceeds, the piece shows a dull-red color in the light, and is 
then said to be red hot. Further heating changes the color 
to cherry red , or bright red, when seen in the light. As more 
heat is applied, the iron changes to an orange and then to a 
lemon color, and finally commences to spark. Just before it 
reaches this point it is said to be white hot, and has a dazzling 
white glow. If heating is continued, the iron will be burned. 

29. Selection of Tools. —A very important point is 
the selection of the proper tongs to hold the work. Not only 
is good work impossible with tongs that do not hold it firmly, 
but their use is dangerous, because the hot piece of material 
is likely to fly out, and may hit the helper or the smith. If 


14 


HAND FORGING 


49 


tongs must remain in the fire while the work is being heated, 
they should be cooled off before any hammering is done on the 
work. A heavy hammer should not be used for light work nor 
a light hammer for heavy work. The hammer should come 
down flat, so that the corner does not make a dent in the work; 
this is very important in finishing. 


30. Use of Sledge. —The helper, in handling the sledge, 
should watch the manner in which the blacksmith uses his 
hammer and should try to follow him. For example, when 

the blacksmith strikes 

/* N 

flat on the work, the 
helper should strike 
flat with the sledge; 
when he strikes at 
an angle, the helper 
should strike at an 
angle; when he strikes 
heavily or lightly, the 
helper should strike 
in the same way. The 
paths of the sledge 
and the hammer are 
shown in Fig. 5. The 
sledge a is raised along 
the dotted line b c and 
descends along prac¬ 
tically the same - line, its blows alternating with those of the 
hammer d , which follows the line b e. 



31. Forging Wrought Iron and Machinery Steel. 
Wrought iron should be as hot. as the material will stand with¬ 
out injury, which is close to a welding heat, and most of the 
hammering should be done while the work is white hot. When 
wrought iron cools down to a red heat it splits easily. The work 
should be hammered from different sides to get the same effect 
of the hammer blows throughout the material. The wrought- 
iron fibers are easily separated, and internal cracks, which do 
not show on the surface, may be the result of improper handling. 


















M9 


HAND FORGING 


15 


32. Machinery steel is more brittle than wrought iron and 
is therefore more difficult to forge. It should be heated care¬ 
fully and should be forged at less than a welding temperature. 
All forging should be stopped when the steel has cooled to a 
dull red, and if the operation is not finished, the work should 
be reheated. The greater the percentage of carbon, the harder 
is the steel; hence, in working steel, heavier blows must be used 
than in working wrought iron, to produce a given effect. If 
a piece of low-carbon steel is heated to a welding temperature, 
when finished it should be reheated to a dull red and allowed 
to cool slowly; in fact, this practice should be followed in the 
case of all forgings made of machinery steel. This material 
can be forged at a low temperature without danger that its 
fibers will separate, as occurs when wrought iron is worked too 
cold. Machinery steel can also be punched without danger 
of splitting. Hence, more drawing out and forging, but less 
welding, is done with machinery steel than with wrought iron. 


DRAWING 

33. Position of Work on Anvil. —In all work on the 
anvil, it must be remembered that the top face is crowned cross¬ 
wise, and the metal will therefore be drawn most readily in 
a direction at right angles to the length of the anvil. If the 



piece is to be drawn lengthwise, it should be laid across the 
anvil as shown in Fig. 6; if it is to be drawn sidewise, it should 
be held as shown in Fig. 7. The drawing may be done by hold¬ 
ing the work across the horn of the anvil; the sharper curve 
causes the metal to flow more freely than on the face, but it 





























16 


HAND FORGING 


49 


is more likely to cause irregularities in the shape. When the 
work is to be straightened, it should be laid lengthwise, as 
shown in Fig. 7, because the anvil is straight in this direction. 

34. The outer edge of the anvil, near the horn, is usually 
made slightly rounded, and drawing may be done by hammer¬ 
ing the work on this part of the anvil. This method saves time, 
but leaves a rough job, and therefore should be used only when 
a considerable amount of drawing must be done on the piece. 
The bottom fuller and the top fuller may also be used for draw¬ 
ing. If the work is to be drawn out lengthwise, the fuller is 
set crosswise on the work; and if it is to be drawn crosswise, 
the fuller is held lengthwise on the work. The piece should be 
supported squarely under the point where the blow is struck; 



otherwise, the effect of the blow will be to sting the hand hold¬ 
ing the work. Also, there is danger that the piece may be 
knocked loose from the grip of the tongs. 

When drawing down the end of a piece, the metal has a 
tendency to curve or lap over the end, which must be counter¬ 
acted by striking so as to draw the metal back; otherwise, the 
overlapping metal will cause checks, or cracks, in the finished 
work and will weaken it. The temperature at which forging 
operations should be carried on should be from a cherry-red 
to a white heat, and no hammering should be done after the 
work reaches a dark red, except in finishing, which may be done 
at a black heat, using light blows. The face of the anvil should 
be kept clean and all scale should be removed from the work. 
The scale cools more quickly than the metal and is harder, 
and may therefore cause pits in the finished work. 






















§49 


HAND FORGING 


17 


35. Round Drawing. —The part of the work to be drawn 
is marked with soapstone and carefully heated to a white heat. 
It is then taken from the fire, quickly brought to the anvil, 
the scale removed, and the work hammered rapidly. The 
diameter may be reduced by two methods: first, by keeping 
the work as nearly round as possible during the entire process; 
and second, by drawing it to a square, then to an octagon, 



Fig. 8 


and then to a round. By the first method, the piece is turned 
a little after each blow and kept as nearly round as possible, 
and finished with the hand hammer or with a swage, as shown 
in Fig. 8, or by using a swage block. A second heat is some¬ 
times necessary. The piece should be turned from left to 
right and then from right to left, because turning it always 
in the same direction is apt to twist the fibers. By this method 
































18 


HAND FORGING 


49 


the iron is liable to split, to avoid which the second method is 
often preferred. The first method is generally used for a small 
amount of drawing, and the second when the diameter mus+ 
be changed considerably. 

36. Square Drawing.— In round drawing, the iron is 
turned a very little at a time, so as to bring all points under 
the hammer. In square drawing, however, the iron must 
always be turned either one-quarter or halfway around. This 
requires some practice, as the least variation in the amount 
of the turn will bring the piece out of square. In drawing a 
square bar down to one having a smaller section of the same 
shape, the sides of the original bar help to guide the hand in 



making the proper amount of turn; but if a round bar is to be 
drawn down to one square in section, the amount of turn must 
be entirely governed by the hand and the eye. In drawing 
down a square bar to a square of smaller size, the piece is heated 
and brought to the .anvil, one of the sides held down flat and 
blows struck squarely on the top side, drawing it down along 
its entire length. It is then revolved one-quarter of a turn 
and the top side hammered until the piece is about square; 
the opposite side is then turned up and hammered; and finally 
the last side is brought under the hammer. The figures in 
Fig. 9 show the order in which the sides are brought under the 
hammer. This method of turning the work lessens the liability 
of getting the piece twisted, or diamond-shaped, as shown in 







































HAND FORGING 


19 


§49 

Fig. 10. If it becomes twisted in this way, it should be held 
and struck in the direction shown. 

37. Another method of drawing out a square, often used 
by experienced blacksmiths, is to heat the work to an even 
cherry red or a little higher, and while hammering, turn the 
work a quarter turn after each blow. After some hammer¬ 
ing the work is given a half turn, and the operation is repeated. 
The work is thus kept more nearly square than can be done 
by the first method, and the fibers of the iron are less liable 
to be separated. 

In all drawing, the work should be so hammered that the 
metal on the outside is not stretched more than that at the 



center, or the end will be cup-shaped. To avoid cupping, 
the work should be properly heated and the blow so heavy 
that its effects will penetrate to the center. The heating 
should be done slowly, so that the work will be heated uni¬ 
formly and thoroughly. The metal draws easier near the 
end; consequently, it is better to start drawing at the middle 
and work toward the end. If this is not done, the work is 
apt to become too small at the end before the fault is noticed. 

38. Drawing to Octagon. —To draw a piece to an 
octagonal, or eight-sided, form, the work is first made square 
and measured to insure that the sides are equal. Each corner 
is then hammered down until the eight sides are of equal widths. 


































20 


HAND FORGING 


§49 


The work should be turned over occasionally, and care should 
be taken not to hammer it while too cold; otherwise, the sides 
that originally formed the sides of the square will be hollow. 

39. Drawing to Hexagon. —In drawing to a hexagonal 
section, two opposite sides of the iron are flattened to about 
the required width of one side of the finished piece. Then one 
of these flattened places is held at an angle of 60° to the anvil 
face and the third and fourth sides are flattened. The piece 
is then turned through another 60° angle and the fifth and sixth 
sides are flattened. The six sides are then finished to the proper 
width. This forging may also conveniently be done by the 
use of a swage block, in which several horizontal slots are cut. 
The slot of the required size is selected, or, if this cannot be 
obtained, the one next larger. The work is heated to nearly 
a white heat, is laid in the slot and struck on the top. It is 
then turned through 60° and struck again on the top. This 
operation is repeated until all sides are finished. A top swage 
may be used in connection with the swage block, if the num¬ 
ber of pieces required is large enough to justify the making of 
such a swage. 

40. Drawing a Ring. —To avoid making a weld, a ring 
may be forged from a piece of flat stock. The stock should 
contain a little more volume than the desired ring. It is first 
cut square and then the corners are trimmed off, forming an 
octagon. A hole is punched through the center and enlarged 
until it will allow the horn of the anvil to enter. The piece is 
then drawn and rounded on the horn until it has the required 
thickness and internal diameter. This method of making a 
ring is particularly useful because a ring so produced is more 
dependable than one that is welded. 


BENDING 

41. In order to obtain good results, the work must be 
heated evenly at the point where it is to be bent. The best 
heat to be used is close to a red heat, but this varies some¬ 
what with the composition of the iron. Too high or too low a 
heat will not give the required results. For instance, a piece 



§49 


HAND FORGING 


21 


will sometimes bend more easily at the place where it is red hot 
than where it is white hot; therefore, an even red heat is neces¬ 
sary at the place where the bend or twist is desired. Small 
sizes of rods may be bent easily 
by inserting them in the hardie 
hole or the pritchel hole of the 
anvil to the point at which the 
bend is desired, and bending 
the end over. Some pieces may 
be bent by doing the work 
entirely over the face of the 
anvil, whereas other pieces are 
bent over both the horn and the 
face of the anvil at various 
stages of the operation. 

42. A very good way of 
bending iron for a band ring, or 
for a similar piece, is to use a piece of J-inch or f-inch round iron 
bent into U shape, as shown in Fig. 11 (a). This piece is 
clamped in the vise with the open end up, and the iron to be 
bent is laid between the projecting ends and bent by pressing 



the end sidewise, as shown in ( b ); or, a fork that has a square 
shank to fit the hardie hole of the anvil, as shown in (c), may 
be used. The iron may be bent either hot or cold. If the iron 



Fig. 11 












































22 


HAND FORGING 


§49 



Fig. 13 


is thin, it should be bent cold, as hot bending is liable to kink 
it. If thin iron is bent hot over the horn of the anvil, the jarring 
from the hammer blows is also apt to make the projecting end 
sag and lose its shape. 

43. If a large number of pieces are to be bent to the same 

shape, a former of special design 
should be used. A former in- 

2 tended to produce elliptic links is 
shown in Fig. 12 (a). It consists 
of two arms a that are pivoted 
on the pins b on which the rollers c are set, but on the opposite 
side of the frame d. The arms carry rollers e that can turn 
freely on the pins/. To use the device, the arms a are swung 
around to the opposite side, as shown by the dotted lines g, 
and a straight piece of wire of sufficient length to form the link 
is placed between the rollers c and e. Then the handles or arms 
are swung around to the position shown, and the wire is bent 
around the rollers c to the desired form, as shown in ( b ). An 
adjustable stop is added between the rollers e at the left, to 
keep the wire from bending back. 

44. Eye Hanger. —Suppose 
that it is desired to form the eye 
pipe hanger shown in Fig. 13, to 
support a pipe lj inches in di¬ 
ameter; the eye is to be bent to 
the form shown, but not welded. 

A rod J inch in diameter and 
slightly over 2 feet long is 
marked at a distance of 6 inches 
from one end; this end is then 
heated to a bright red up to the 
point marked. The cool end of 
the rod is grasped with the left hand, and the marked point 
on the heated end is placed over the farther edge of the 
face of the anvil, or over the horn near its point. The heated 
end, which projects, is then bent down so that it points nearly 
at right angles to the rest of the rod. The rod is then turned 





















































































§49 


HAND FORGING 


23 


on its axis halfway around so that the heated end points up 
instead of down. The extreme end of the heated part is then 
brought down so that it projects slightly 
over the end of the horn, as shown in 
Fig. 14, and the end of the rod is bent 
gradually by light hammer blows into a 
ring, as shown in Fig. 13. If desired, it 
may be shaped around a pin of suitable 
diameter, used as a mandrel. 

45. Forging a Staple.—If a staple, 
like the one shown in Fig. 15, is to be 
made from a piece of J-inch round iron, 
the required length is first marked off on 
the bar. On this, a distance of 1 inch 
from the end is marked off, and the end 
is heated and drawn to a square point 
If inches long. The piece is then cut 
off from the bar, using the hardie, as shown in Fig. 16, and 
making the piece 5J inches long, over all. The other end is 

marked and drawn out 
to a point the same as 
the first, keeping both 
squares in line. The 
piece will now be about 
6f inches long, f inch 
round in the middle, with 
a square tapering point 
If inches long at each 
end. The center of the 
piece is then marked and 
heated, and the piece 
bent over the horn of the 
anvil to the shape shown 
in Fig. 15, making the 
distance between the two 
straight, parallel ends f inch. In bending over the horn of the 
anvil, the piece is held against the large part of the horn and 




205—6 































































24 


HAND FORGING 


49 


bent by light hammer blows, turning it to keep it round; then 
while hammering it the piece is gradually brought toward the 
point of the horn. When bent, the curve should be uniform 



and the two ends of the same length. If it is warped or twisted, 
it is flattened on the anvil with the hammer or the flatter. 

46. When drawing the stock for the staple to a point, 
great care must be taken to avoid splitting. After heating it 
to a very bright red, drawing is started from the end, working 
from two sides in order to make a square point. The work 
should be held at an angle to the anvil and struck at the same 
angle to the anvil. If the piece must be replaced in the forge 
for a second heat, care must be taken not to overheat the drawn- 
out part, which will heat more quickly than the larger body, 
especially when the point is slender. The work should not be 
hammered when below a red heat, or it will very likely split. 


TWISTING 

47. Forging a Gate Hook. —If a hook, like the one shown 
in Fig. 17, is to be made of J-inch square iron, the operation will 
be about as follows: As about 4 inches of stock is required to 
make the hook, this length is marked off from the end. It is 



then heated and drawn out until it calipers | inch square, 
when it will be about 5J inches long. A length of If inches 
is then marked off from the end and drawn first octagonal 














































49 


HAND FORGING 


25 


and then to a round of j^-inch diameter, keeping one side 
straight, as shown at d, Fig. 18. The shoulder, or offset, / is 
formed over the edge of the anvil, as shown in Fig. 19. By 
striking the upper edge 
with the hammer, as 
shown, the top will re¬ 
main straight at d, after 
which it can be finished 
with a swage to make it 
perfectly round. A 
length of f inch is then 
marked off on the ^--inch 
end and the point drawn 
down round, as indicated 
by the dotted lines, 

Fig. 18. The entire piece 
is then cut from the bar 
and the other end of the f-inch square marked off, making 
the distance between the shoulders 2f inches, and drawn to 
\ inch round, keeping it straight at e and forming a shoulder 
at h. The J-inch round part is bent into a ring over the 
horn and the ^--inch round end is bent into the hook, as 
shown in Fig. 20. In bending the hook and the ring, the 
piece is held with one round end projecting over the farther 
edge of the anvil, and this projecting end is bent back until it 
has the shape shown in Fig. 21. The other end is then bent 
in the same way, and the ring and hook formed over the horn 




of the anvil by light hammer blows, which should not fall 
directly on the place where the work rests, but a little beyond 
this point. The stock will thus be bent without destroying 
its shape. 
























HAND FORGING 


§49 


26 


48. Twisting the Hook. —Lengths of \ inch are now 
marked off with a prick punch on the square part from the 
shoulders / and h, giving the points k and p, Fig. 20. The 


Fig. 21 




portion between k and p is then brought to an even red heat 
and twisted. To do this, the piece is clamped vertically in the 

vise by the hook end, as 
shown in Fig. 22, with the 
point k at the top edge of 
the vise jaw, and a monkey- 
wrench is fitted to the ring 
end, immediately above the 
point p. The wrench is 
then given one complete 
turn, twisting the square 
part as shown in Fig. 17. 
If it has become bent, it 
may be straightened by 
hammering it between two 
blocks of wood on the anvil 
so as to avoid battering 
the sharp edges. For light 
work, two pairs of flat 
tongs may be used for the 
twisting, one pair to take the place of the vise and the 
other pair to do the turning. 



















































£49 


HAND FORGING 


27 


UPSETTING 

49. Ramming. —When it is desired to upset, or thicken, 
a portion of a piece of iron, this part is heated to almost a white 
heat, the rest of the bar being kept cool by pouring water over 



Fig. 23 


it with the sprinkler, or by dipping it in water. When suf¬ 
ficiently heated, the piece is brought to the anvil and upset, 
either by ramming or with the hammer. 























































28 


HAND FORGING 


49 


If the bar is from 2 to 3 feet long and is to be upset at the 
end, the heated end of the bar is rammed against the face of 
the anvil, as shown in Fig. 23, or on a block of iron bedded 
in the ground, called a bumping block. The entire energy of the 
blow is concentrated at the hot end of the rod, and drives 
the particles of the iron near the end together in the direction 
of the blow, thus bulging out the iron where it is hot. 



Fig. 24 


50. Upsetting With a Hammer.—If the bar is short, 
it may be brought to the anvil with a pair of tongs, as shown 
in Fig. 24, and held vertically on the anvil with the hot end 
up and the heated end hammered, or with the hot end down 
and the blows struck on top of the cold end. By the second 
method, the heated end is constantly in contact with the cold 
face of the anvil and will therefore cool very rapidly; con¬ 
sequently, the bar will spread less at the end, but the bulge will 







































§49 


HAND FORGING 


29 


extend up a little further than by the other method. In the 
same manner an upset may be made at any point on the bar 
by heating the place to be upset, while the remainder is cool. 



51. Precautions in Upsetting. —If, in upsetting a bar, 
it begins to bend after a few blows have been struck, the piece 
must be straightened at once, for any blows struck endwise 
on a bent bar will have little effect in upsetting it, but will 
only bend the bar more and make the straightening harder; 



Fig. 26 

therefore, good square blows must be struck. For upsetting, 
a good heat is required; in fact, it is well to make the final heat 
a welding heat, because upsetting often separates some of the 












































































30 


HAND FORGING 


49 


fibers, and by taking a welding heat over the piece and hammer¬ 
ing it on the sides a little, all loose fibers will be welded together 
again. 


52. Square-Headed Bolt.—If a J-inch bolt, Fig. 25, is 
to be made from a ^-inch round rod, the end of the rod is heated 
and upset. Bolts should be headed at as near a welding heat 
as the iron can be worked. When enough metal has been upset 
to form the head, the cold end of the bar is passed through a 
suitable hole in the swage block, or through the heading tool. 
If the latter is used, it is laid on the anvil so that the body of the 

bolt passes through the 
hardie hole. The upset 
end is then hammered 
down against the swage 
block or heading tool, as 
shown in Fig. 26, until 
the head is inch thick, 
and the piece is driven 
out of the heading tool. 
The head is then shaped 
square with a hand ham¬ 
mer. If, after the sides 
of the head are properly 
formed, it is found that 
the head is longer than 
it should be, it is laid on 
a piece of soft iron placed 
on the anvil and the extra length cut off with the hot cutter. 
The bolt is then put back into the heading tool and the head 
is finished with the hammer; the bolt is then cut off to the 
desired length, and the burrs, or rough edges, on the end are 
hammered down. 



Fig. 27 


53. A bolt header, shown in Fig. 27, may be used in 
upsetting the end of the bar to form the stock for the head. It 
consists of two uprights a and b, the latter of which is pivoted 
on a pin c so that its top can be swung toward or away from the 
top of the upright a, The dies d and e are set in the tops of the 


































































§49 


HAND FORGING 


31 


uprights and are forced apart by pressing on the pedal / with the 
foot. The heated stock for the bolt is then set between the 
dies, with its lower end resting on the adjustable block g, and 
the pressure on the pedal is relieved. The weight h then falls, 
moving the tops of the uprights together and closing the dies 
around the upper end of the bar, which projects somewhat 
above the dies. This heated projecting end is then ham¬ 
mered down to the desired thickness of the bolt head, after 
which the dies are moved apart and the bolt taken out. The 
machine is provided with a set of dies to suit stock of different 



Fig. 28 

sizes. Bolts of different lengths are accommodated by moving 
the block g up or down and clamping it in place by the screw i. 

54. When in use, the dies of the bolt header should be 
carefully set in line, as shown in Fig. 28 (a). If they are out 
of line, as in ( b ), fins will be formed along the opposite sides of 
the bolt, as at a in view ( c ). Pieces of sheet iron may be 
inserted at the sides of the dies to bring them into line. Blows 
should fall squarely on the end of the bar to be upset, and the 
finished work will then appear as in (d). If the blows are 
not square, the head will be formed to one side, as in (e). After 
































































































































































































































32 


HAND FORGING 


49 


the bolt has been upset, as shown in (d), it is taken out of the 
machine and squared on the anvil, after which it is put back 
in the header and hammered to bring the head to the correct 
thickness. A tool like that shown in (/) is used finally to round 
the surface of the head; it is set on the upset head and struck 
on the end a. 





55. The iron must not be burned by overheating, or the 
part of the bolt just beneath the head may be wasted away 
and become too small. The same defect may be caused by 

using too small dies. The stock for the 
bolt should be heated far enough from the 
end to allow the dies to grip hot metal; 
otherwise, it will not upset properly and will 
form a weak head. It should not be heated 
too far, however, or it will buckle between 
the dies and the supporting block, making 
the upper part too short. The edges of the 
dies should be rounded slightly, so as to 
leave a fillet where the stem of the bolt 
joins the head. The upsetting should be 
done at one heat, if possible. The size of 
a bolt is given by stating the diameter of 
Fig. 29 the stem an d its length under the head. 

For example, a f-inch bolt 8 inches long 
has a stem f inch in diameter and 8 inches long, measured 
from the under surface of the head to the end of the bolt. 


a 


'b' 


T~ 

"Vj 


d c' 


56. T-Headed Planer Bolt.—Suppose that a planer bolt 
of the size and shape shown in Fig. 29 is to be made from a 
|-inch round rod. The operation consists in alternately upset¬ 
ting the end and forging it to the oblong form of the head 
indicated by aecf in the top view. The points abed of 
the head in the top view correspond to the points a' b' c' d f 
in the side view. The end of the rod is first heated and upset; 
the upsetting must alternate with hammer work to keep the 
sides af and e c parallel. For the latter, the bolt is laid flat 
on the face of the anvil with first one side e c placed upper¬ 
most to receive the blows of the hammer, and then the opposite 










§49 


HAND FORGING 


33 


side. Also, the head is frequently moved beyond the edge 
of the anvil and is struck with the hammer for the purpose of 
both forming and upsetting it. 

57. The process of upsetting and forming is continued 
until the amount of metal upset is sufficient to form the desired 
head. This is then heated and the cold end of the rod is passed 
through the right size of hole in a swage block, or through a 
heading tool, and the inside face of the head is worked to shape. 
But this latter cannot be done at one operation, for the side 
faces, shown in the top view at a e and c /, Fig. 29, must be 
brought to shape with the hammer. The final shape of the 
head, shown in the top view by a e c /, is obtained by dressing 
the side faces a e, e c, c /, and / a and the end face of the head 
with the hammer, and by finishing the inside face on the swage 
or heading tool. The lengths e b and / d , each equal to \ ifich, 
are marked off with a soapstone pencil or a hand chisel and the 




portions of the head aeb and cfd are then cut off with the hot 
cutter. The angles bad and bed are approximately equal 
to 65°, and hence if the bevel is used it may be set to this angle 
and used to test the angles between the faces. It is not desir¬ 
able that the edges at a and c be made sharp. The head of 
the bolt is made thin so that it will break off before the pres¬ 
sure becomes great enough to injure the lip of the T slot in the 
planer table. 

58. Making a Hexagonal Bolt Head.— If it is desired 
to form a hexagonal head on a J-inch bolt of the dimensions 
shown in Fig. 30, the end of a f-inch round rod is heated and 
upset. When enough metal has been upset to form the head, 
the cold end of the bar is passed through a suitable hole in the 
swage block or the heading tool, and the inside face of the head 
is surfaced around the shank of the bolt as described for a 
square-headed bolt. 















34 


HAND FORGING 


49 


The head is then shaped in a three-sided groove of proper 
size, which is usually formed on the edge of the swage block. 
The swage block is placed so that the groove is horizontal 
and the opening is on top. The inside face of the head is trued 

up, as before, and the side faces are again 
touched up with the swage, after which the 
head, if it is too long, is marked for the 
proper thickness and the end cut off with 
the hot cutter. A hand hammer is also 
used in the final dressing of the head. 
A cup-shaped swage may be used for finishing the top of the 
head into the rounded shape shown in Fig. 31. The bolt is 
finally cut to the proper length, which in this case is 5 inches, 
and the burrs on the edges are dressed down with the hammer. 

Iron bolts can be made from bars of the same diameter as 
the diameter of the bolt, the heads being made by welding 
on rings or by upsetting the stock. Tool-steel bolts must be 
made from bars as large or larger than the head, and the body 
drawn down to the required size. 

59. Making a Small Chain Hook. —If the chain hook, 
shown in Fig. 32, is to be made from a bar of |-inch round 
iron, about 6| inches of stock is required. The end must be 
upset to provide stock for the eye of the 
hook. To provide enough stock to make 
the eye, a length of 1^ inches is marked 
off from the end of a bar, and the end 
heated and upset until the original lj-inch 
length is shortened to 1 inch. The piece is 
then flattened down to f inch in thickness, 
making the upset portion circular and about 
1 inch in diameter, as shown in Fig. 33. 

60. In flattening the upset portion to 
f inch in thickness, it should be spread 
sidewise as much as possible. If it draws out in length, it 
may be upset a little in a swage or heading tool, or on the 
edge of the anvil, as shown in Fig. 34. When the head has 
been formed, it is heated, and a J-inch hole put through 



Fig. 32 



Fig. 31 

















HAND FORGING 


35 


§ ±9 

with the punch, which should be kept cold by dipping it in 
water before and after it is used. After the hole is started, 
the punch is held aside to see whether it is in the center; if it 



is, the punch is driven down well and the piece is turned over 
and punched from the other side, where the iron shows a black 
circular spot. The core is driven out through the hardie hole 
or through the pritchel hole. Some smiths put a little coal 
or coke dust into the hole after it has been started and then 
finish the hole by driving the punch on top of it; the point of 
the punch is thus kept cool and prevented from sticking in the 
hole. 


61. When the hole has been punched, the eye of the hook 
is raised to a welding heat and worked over to weld up any 
parted fibers or split places. For this, the punch is put into 
the hole and left there while hammering the eye. The punch 
is driven down occa¬ 
sionally to keep it 
tight; the hole will thus 
be spread to about 
f inch in diameter. 

Another method of 
making the eye is to 
take a sufficient length 
of material to form 
the eye of the hook 
by bending the end 
of the rod around a 




pin, a mandrel, or the 

end of the horn of the anvil. The eye end of the rod is first 
scarfed as shown at a, Fig. 35 (a), and is bent around to form 
the eye as shown in ( b ), after which the end is welded 




































36 


HAND FORGING 


49 


These latter operations will be described in detail in con¬ 
nection with welding operations. 

62. The first step in bending the hook to shape is to bend 
the point, or small end. Then the heavier middle section is 





heated, the point is dipped in water to cool it, and the body 
of the hook is bent over the horn of the anvil, at a point about 
one-third the distance from the tip to the eye. The work is 
then turned over so that the back rests on the anvil and blows 
are struck near the tip, thus completing the bend and closing 
the hook to the desired amount. Finally, the neck is heated 

and bent over the horn 
of the anvil so that the 
center of the eye and the 
point where the load 
hangs on the hook will be 
in the same vertical line 
when the hook is in use. 

To reduce the labor of 
forging, a chain hook 
may be made of flat 
stock. One end is formed 
to the shape of the point 
of the hook and a hole 
for the eye is punched 
at the other end. The 
neck is formed by laying the piece edgewise on a bottom fuller, 
placing a top fuller on the upper edge, and striking it with a 
sledge. The eye is then rounded over the horn of the anvil, 
















§49 


HAND FORGING 


37 


the neck is rounded and tapered out into the body of the hook, 
and the heavier section is forged to a wedge shape. The bend¬ 
ing is then done as already described. 

63. Upsetting a Ring. —If a ring stretches or is made too 
large, it may be made smaller by the process of upsetting. 
One way of doing this is to heat a part of the ring to a bright 
red, as at a, Fig. 36, lay it on a piece of round iron b and bend 
it over this piece as shown. It is then set in the vise and gripped 
by the jaws at the points c and d, so that the bend a projects 
above the jaws, and is struck at the points e and/ in the direc¬ 
tions indicated by the arrows. The hammering at / upsets 
the metal at g and that at e upsets the part h, thus shortening 
the ring. The ring is now removed from the vise and the bend 
is hammered back to its original shape over the horn of the anvil. 
The amount of upsetting done in the vise should be somewhat 
more than is required to bring the ring to the desired size, as 
there will be some stretching when the ring is hammered back 
to shape. 


SHRINKING 

64. When a piece of iron or steel is heated, it grows larger, 
and when it cools, it shrinks. This action is made use of when 
parts of machines are joined or held together by shrinking 
bands or rings around them. The band or ring is first made of 
the required size and shape. When cool, it is a little too small 
to fit over the pieces to be joined. It is heated to a red heat, 
and the heating causes it to expand about ^ inch for each 
inch of length. This increase of size allows it to be slipped 
into place over the pieces that are to be held together. As 
the ring cools, it shrinks, and in so doing it grips the pieces 
tightly and draws them together very firmly. 













































Serial 1687B 


HAND FORGING 

(PART 2) 


Edition 1 


FORGING OPERATIONS— (Continued) 


RIGHT-ANGLED BENDS 


1. Making Sharp Corner. —If a bar of f-inch square 
iron is to be forged into a right-angled bend with a sharp 


h 




v Kl 




JT 


comer, like that shown in 
Fig. 1, the bar must be upset 
at the center in order to give 
the additional stock re¬ 
quired for the corner. About 
8f inches of stock is cut off, 
and the center is heated and 
upset to | inch in diameter, * 
as shown in Fig. 2. The 
piece is then bent at right 
angles in the center by stick¬ 
ing one end through the 
hardie hole down to the heated center and bending the other 
end toward the anvil, as illustrated in Fig. 3. To make 


Fig. 1 



Fig. 2 


the comer sharp, the piece is held on the face of the anvil, as 
shown in Fig. 4, and the angle made true by hammering. When 

COPYRIGHTED BY INTERNATIONAL TEXTBOOK COMPANY. ALL RIGHTS RESERVED 

§50 


205—7 























































HAND FORGING 


50 




striking the blows the hammer is drawn as shown by the arrow; 

this draws the iron toward the comer. 

« 

9 

2. Care should be taken not to start a nick on the inside 
of the bend, because this will break some of the metal and start 
a crack. When this crack is closed up by forging and by the 
contraction of the metal during cooling, it cannot be seen, and 



then forms what is called a cold shut. To avoid this, the piece 
should be hot enough to bend well and should be bent over a 
rounded place. The angle should be kept a little larger than 90° 
until the outer comer is forged sharp, and then closed up to a 
right angle. The piece is finished f inch square with the 
flatter, and the ends are cut to equal lengths on the hardie, and 
then squared with the hammer. 





















































§50 


HAND FORGING 



,ili! I * "I- * ,i 

/' y y i 


Fig. 4 


3. Besides upsetting, several other methods of obtaining a 
sharp comer may be practiced. Welding in a piece, as indi¬ 
cated in Fig. 5, is a 
quicker process than up¬ 
setting, and if correctly 
done makes a good, solid 
comer. The piece is bent, 
the inside angle squared, 
a gash cut in the piece 
with a hot chisel, and a 
blunt, thick wedge driven 
in and welded, after 
which the outside comer 
or angle is made square. 

Another method often 
used is to split partly 
through the center a 
piece of twice the re¬ 
quired width, as shown in 
Fig. 6. One upper comer is cut off and the one half is bent? 
out and up until it is at right angles to the other half. The 
outside of the comer is then squared. 

4. Forging a Rod Strap. —To make a rod strap of the 
form shown in Fig. 7 (a), it is necessary to use stock of the 
width shown at a in (b), and thicker than b by a sufficient amount 

to form the comers b, view (c). 
This stock is drawn to the form 
shown in (c), leaving the sides 
slightly thicker at c than they 
will be in the finished strap, as 
they will draw in the bending, 
and being careful that the ham¬ 
mer leaves no ridges, which would 
tend to start cracks, sometimes 
called gaulds, in the corners, 
which become deeper as the work progresses. Next, the stock 
is gripped in the tongs, and while held as indicated in (d), is bent, 


V 

vt 


Fig. 5 


Fig. 6 






































































Fig. 7 


4 














































50 


HAND FORGING 


5 


using a large fuller to start the bend, as by starting in this way 
the iron is not cramped at the comers. Any ridges left by the 
hammer may be taken out by the fuller when starting the bend. 

5. After the bends have been started as shown in Fig. 7 (d), 
the stock may be held in the steam hammer in the manner 
shown in (e), by lowering the upper die d on the upper one 
of two blocks b and c, between which the stock is placed, and 
holding it firmly by means of the steam pressure. Next, two 
helpers, one on each side, strike simultaneously on the ends 
until the piece has the form shown in (/). A heat is taken on 
one comer by placing the side 5 down in the fire, and by using 
the flatter, the side is brought to the shape shown in (g ), and this 
is repeated on the other comer and side. During this operation 
the flatter must be used on the strap, which is held as indicated 
in Qi ), in order to make the end of the proper shape. If no steam 
hammer is available, the stock may be bent over a mandrel of 
suitable size or over a square bar held in the vise. 


WELDING 


CONDITIONS GOVERNING WELDING 

6, Object of Welding. —It is often necessary to join 
together two pieces of iron, or the ends of the same piece, so 
that the joint will form one solid mass. In such cases, the 
pieces are welded together. 

Each of the pieces treated thus far has been made of a single 
piece of iron, but very frequently it is inconvenient or imprac¬ 
ticable to make the forging from one piece. In such cases, 
several pieces are welded together, and the forging is said to 
be built up. 

7. Oxidation of Iron. —A piece of iron heated in air 
absorbs oxygen from the air, thus forming a scale of oxide 
of iron on the surface. The hotter the iron, the more rapidly 
the scale will form. It does not stick to the iron very firmly, 
but surfaces coated with it cannot be welded. It is therefore 




6 


HAND FORGING 


50 


very important to guard against scale on the iron if a weld is 
to be made, because the scale will lie between the two surfaces 
of the iron and prevent their coming in contact; and if it is not 
made fluid it will not squeeze out when the pieces are pressed 
and hammered together. Two methods are employed to guard 
against the oxidation, namely, the use of a reducing fire in 
heating, and the use of suitable fluxes. By both of these 
methods the oxygen of the air is prevented from coming in 
contact with the hot iron and thus forming scale. 

8. Reducing Fire. —A reducing fire is one in which all 
oxygen is used in the combustion, so that the gases coming in 
contact with the iron contain no oxygen that can unite with 
the iron. Hence, no oxidation can take place, and no scale 
is formed. This condition is obtained in a closed fire by having 
a thick bed of fire for the air to pass through before coming in 
contact with the iron and by maintaining a moderate blast. 
If, however, the blast passes through a thin bed of fuel or if 
more air is blown through than the fire needs, the unused oxygen 
will oxidize the iron. Therefore, a thick fire should always 
be maintained, and the blast regulated so as to supply just 
enough air and not too much. 

9. Fluxes. —The other method of preventing oxidation is 
to coat the surface of the iron with some substance that will 
exclude the* air. It must, of course, contain no oxygen that 
will unite with the iron. It must be fluid at a heat below the 
welding heat of iron and still not become so fluid at the welding 
heat that it will run off and leave the iron exposed as before. 

Substances used to prevent the formation of scale on iron that 
is being heated for welding are called fluxes. Most of them 
form a fusible mixture with the iron oxide, which affords the 
desired protection to the iron; but to make this mixture some of 
the iron is used up and therefore wasted. This mixture is so 
liquid that it can be squeezed from between the surfaces being 
welded, which are thus left clean. 

10. There are many kinds of fluxes, some of which consist 
of mixtures of several substances. The most common flux for 


§50 


HAND FORGING 


7 


wrought iron is clean sharp sand, which fuses readily on the 
surface of the iron and sticks to it during the heating, thus 
excluding the air. A very good flux for iron, but one that 
cannot be used on steel because it tends to reduce the carbon, 
can be made by mixing 2 ounces of calcined borax and 1 ounce 
of sal ammoniac. The welding of steel is a difficult operation, 
and the best of fluxes should be used; hence, calcined borax 
is commonly employed as a flux for steel. It is made by heating 
borax in an iron pot until the water is driven off. The mass 
is then cooled and pulverized. Calcined borax is also called 
borax glass. 

11. Sand and borax are very good fluxes for iron alone; but 
it is well to have a flux that can be used when welding steel to 
iron. A very good flux for welding steel to iron is made of 
potter’s clay, wet with strong brine. This is dried and powdered 
and used like sand or borax. Another good flux that is not 
too fluid, and does not injure steel, is made by mixing 3 ounces 
of carbonate of potash, also called pear lash, with 1 ounce of 
dry clay. This is heated in an iron pot, and when hot, 4 ounces 
of calcined borax is added. When cold, it is powdered, and is 
then ready for use. 

12. Welding of Steel. —When welding steel, great care 
must be taken to keep the fire deep and clean and not to use too 
strong a blast. If steel is to be welded to wrought iron, the 
pieces must be heated to different temperatures. Both are 
brought to a red heat and borax or some other flux is put on 
them. The heating is continued until the iron is white hot and 
the steel has a bright yellow color. Then the pieces are with¬ 
drawn, put together, and welded with quick sharp blows. Mild 
steel can be made white hot, but care must be taken not to burn 
it, as its strength and toughness will be largely destroyed. 
Steel containing more than 1 per cent, of carbon may be brought 
to a yellow heat; but if the percentage of carbon is greater, only 
a cherry red should be used. Steel containing more than 
1J per cent, of carbon is hard to weld, but the welding can be 
done if the proper care is taken with the fire, the heating, and 
the fluxing. One way of determining when the pieces have 


8 


HAND FORGING 


50 


been brought to the proper temperature for welding is to run 
the poker over them while in the fire. If the poker sticks to 
the work, the correct temperature has been reached. 

13. Tool steel, while being heated for welding, should be 
kept from the air. A low welding heat is required, and the 
steel should be heated in a coke fire. If coal is used, the sulphur 
in it will make welding impossible. The flux for tool steel may 
be made of \ pound of borax, J pound of carbonate of potash, 
and a small quantity of powdered glass, which are melted 
together, and when cold are pounded fine. Some of this flux 
is applied before the work is put in the fire and more while it 
is being heated. The flux will dissolve any oxide that forms. 
Uniform distribution of the flux over the surface of the iron 
will give better results, and may be obtained by using a flexible 
wire gauze, on each side of which a fluxing agent has been 
uniformly applied. The gauze is of the same material as the 
pieces to be welded and is placed between them. During the 
heating the fluxing agent generally passes off as a gas, while 
the wire gauze melts and unites with the surfaces. 


CLASSIFICATION OF WELDS 

14. The different kinds of welds are named according to 
the manner in which the pieces are put together; they are called 
scarf welds , butt welds , lap welds , cleft welds , or V welds , jump 
welds , and fagot welds. The selection of the weld to use depends 
on the form of the piece, the forces it is to resist, and the equip¬ 
ment for making the weld. 



15. Scarf Welding.—In the scarf weld, the two pieces 
are scarfed; that is, they are thinned down, as shown in the 
pieces a and b, Fig. 8. If the iron is of uniform thickness, it 
is first upset at the point at which the weld is to be made in 






























50 


HAND FORGING 


9 


order to gain a little in thickness; after this, it is scarfed. To 
do this, the upset end is thinned down, generally with the peen 
of the hammer, drawing it out thin at the point and crowding 
the metal back at the stock by 
drawing the hammer as shown at 

a, Fig. 9. Sometimes the end of a 
flat bar, after being upset, is tapered 
or scarfed by using a fuller, as shown 
in Fig. 10, which is a quick and 
effective way. The faces to be 
welded should be rounded and made 
higher at the center, as shown at 

b, Fig. 9, so that the pieces first come 

in contact at this point, in order to 
squeeze out the flux and impurities 
as the weld is being closed. fig. 9 

16. In heating work for welding, careful attention should 
be given to the fire and the blast. A good body of live coal 
must be kept below the work. Green coal, which contains 

gas, tar, and sulphur, should 
never be thrown on the fire 
during the heat, because 
this treatment will spoil the 
heat. If clean foundry coke 
can be obtained, a small 
amount broken up and 
mixed with forge coke will 
help to produce a solid fire. 
Foundry coke is slow in 
burning, and will deaden 
the fire, if too much is used. 
In welding, a moderate 
blast is employed. A little 
welding flux is sprinkled on 
the work directly after scarfing, if a flux is used; this brings 
the flux over the material before it has time to scale. If 
some flux is required later, the work is taken out just before 



Fig. 10 





























































10 


HAND FORGING 


50 


it reaches a welding heat, the scale is rubbed off and the 
flux is applied. The heat should be given time to soak 
in, and the blast pressure should be increased slowly. When 
the proper heat is reached the surfaces of the metal will shine 
and appear as though melted iron were running off them. If 
the pieces are brought together in the fire, they will adhere. 
Great care must be taken to heat the work evenly, and the 
heavier parts should be heated first. The work of welding will 
be greatly facilitated if the pieces are heated well back of the 
welding point, whenever possible. 

17. The scarfed ends of both pieces having been brought to 
a welding heat, and fluxed if necessary, the weld is made as 
follows: The shorter piece is gripped with the tongs m the 
right hand and the longer piece in the left, the scarfed faces of 

both being downwards in 
the fire. Both pieces are 
drawn out at the same time 
and each is rapped smartly 
against the anvil to knock 
off any coal or other sub- 
) stance that may adhere to 
the heated surfaces. The 
shorter piece is brought to 
the position on the anvil shown at a, Fig. 11 (a), and is followed 
with the longer piece, which is brought to the position of the 
dotted outline b. Then, without losing contact between the 
longer piece and the anvil, the piece b is brought down on 
the piece a, as shown in (b). If the piece b is rested against 
the edge of the anvil, as indicated by the dotted lines in (a), 
and is rocked to the position indicated by the full lines, the 
pieces may easily be brought together in their correct relative 
positions. 

18. After the piece b, Fig. 11 (a), has been properly placed 
on the piece a, a slight pressure on it will hold both in position 
while the tongs are dropped and the right hand relieved so 
that the hammer may be taken and a light blow delivered in 
the direction of the arrow c, view (6). As soon as the pieces 











50 


HAND FORGING 


11 



Fig. 12 



Fig. 13 


adhere, the ends of the scarf may be brought down by delivering 
a few light blows on one side, and then the piece turned over and 
the other side struck in the 
same manner before it has 
cooled below the welding 
heat. If the scarfs are 
made too long, the surface 
to be welded is increased and useless labor is involved. All 
work, after the piece is removed from the fire, should be 

done as quickly as possible. 

19. Butt Welding. 

The butt weld is used for 
heavy work only. The 
pieces to be welded are 
upset at the ends and the end faces are made slightly rounding, 
or convex, as shown in Fig. 12. The pieces are then put in the 
fire from opposite sides of the forge, so that their ends face 
each other, as in the illustration, and they are brought to a 
welding heat. Flux is added to keep the surfaces clean. When 
a welding heat is reached, the pieces are driven 
together while in the fire, until they unite. 

They are then removed quickly and carefully 
and finished on the anvil or under the power 
hammer. The convex ends allow the slag to 
escape readily when the pieces are driven to¬ 
gether in the fire. 

20. Lap Welding. —In making a lap weld, 
the two pieces are laid together face to face, 
as shown in Fig. 13, and welded. As the faces 
are not rounded, the hammering is started at 
the center and gradually carried toward the 
edges, in order to work out all the slag. If the 
edges are welded and any slag remains between 
the faces, the metal will be prevented from 
uniting in the center. 

21. Cleft Welding. —When a weld is required to stand 
considerable strain, such as is caused by prying and bending, 



Fig. 14 









































































12 


HAND FORGING 


50 


or when the weld must be made in the fire, the pieces are gener¬ 
ally joined by the cleft weld, shown in Fig. 14. One of the 
pieces a is upset to gain width and thickness, is split open on 

the end, as shown at a, and the 
two cheeks c and d are spread 
apart; the other piece is then 
scarfed on both edges, as shown 
at b. In welding, the pieces are 
first hammered on end to get the 
weld to stick, which may be done 
in the fire; they are then ham¬ 
mered on the edges to close the 
weld. The angle of the piece 
that enters should be smaller 
than that of the other piece, so 
that the point / will touch and weld first, and the slag be forced 
out as the sides c and d close down. 

22. Jump Welding. —The jump weld is really a special 
form of cleft weld. If a bar is to be welded to a flat plate, a 
conical depression is made in the plate as shown at a, Fig. 15. 
The bar to be welded is pointed as shown at b. The two 
conical surfaces must be so formed that the parts will come 
together at the point first, so that any slag will be squeezed out 
as the piece is driven, or jumped, into its seat. This form of 
weld is frequently used for quite large work, the bar being driven 
into place under the steam hammer. 

23. Building Up. —It is frequently inconvenient or 
impracticable to make a 
forging out of a single 
piece because of the shape 
it is to have. In such a 
case the forging is built 
up; that is, it is made of 
a number of pieces that 
are forged to their approximate shapes and then welded together. 
Fig. 16 shows a built-up forging in which the welds are desig¬ 
nated by the letters a. 




Fig. 15 



















































§50 


HAND FORGING 


13 


24. Fagot Welding. —Two or more layers of metal must 
sometimes be welded together in order to get a piece of stock 
heavy enough to form an enlarged part, or boss. For this 
purpose, the piece may be doubled over on itself, or separate 
pieces may be welded together. The surfaces to be welded 
must be clean and free from scale. The flux should be put on 
as soon as the pieces are hot enough to make it fluid, and 
hammering should start at the center, in order to squeeze out 
the impurities. 


WORK INVOLVING} SCARF WELDS 

25. Making a Corner Plate. —In order to illustrate some 
of the applications of the scarf weld, a few simple cases, in 
addition to those already given, involving the various principles 




V 


hH 


(a) 




of welding in general and of scarf 
welding in particular, will be 
^ described. 

If a comer plate, like the one 
shown in Fig. 17 (a), is to be 
made, two pieces of §"X li ,; iron, 
each about 15 inches long, are 
heated at one end, one being 
kept near the edge of the fire 
so as to heat it more slowly than the other. When hot enough, 
one is taken from the fire, and the end upset and then scarfed, as 
shown in ( b ). This is done by striking it, and at the same 
time drawing the hammer toward the hand, as shown in Fig. 9. 







































14 


HAND FORGING 


50 


in order to draw the metal that way. The other piece is then 
taken from the fire, upset at the end, and one edge scarfed as 
shown in Fig. 17 (c). 

26. When both pieces are ready, they are put into the fire 
and raised to a bright-red heat, being turned occasionally to 
get the heat even. They are then dipped into the flux or the 
flux is sprinkled over their surfaces and they are returned to the 
fire and raised to a good white heat on the scarfs. The pieces 
are turned occasionally to prevent the flux from dropping 
off. As soon as both pieces approach a welding heat, the blast 
is turned on stronger in order to raise the final heat rapidly; 
and if necessary, a little more flux is thrown on the pieces while 
in the fire. When hot enough, the pieces are brought to the 
anvil and put together, being held against the edges of the anvil, 
somewhat as in Fig. 11, care being taken not to touch the cold 
anvil with the heated portion. When the scarfs are in line, the 
pieces are brought down flush on the anvil, having the piece 
in the right hand below the one in the left hand, so that the 
left-hand piece will be able to hold the other down while the right 
hand does the hammering. After the pieces stick, they are 
turned over to bring the other face under the hammer. 

27. The form of the scarf should always be such that the 
centers of the surfaces to be welded come in contact first; the slag 
will thus be squeezed out as the pieces are hammered together. 
As soon as the pieces cool to a cherry red, they are reheated 
and the weld finished. When black hot, both sides of the 
piece are struck against the horn to make sure that the weld 
is well made. A good weld will not open on being bent and 
then straightened. If the weld is good, the corner is tried with 
a try-square and finished perfectly sharp and square, on the 
edge of the anvil, as shown in Fig. 17 (a). The ends are then 
cut off, making each arm 5 inches on the long edge. A fillet 
at the inside comer will add considerably to the strength. If 
the finished comer is to be more or less than a right angle, the 
scarf and lap should be made accordingly. 

28. Making a T Plate. —A T plate like the one shown in 
Fig. 18 (a) can be made in nearly the same way as the corner 


50 


HAND FORGING 


15 


plate. 1'he crosspiece a is scarfed as shown in ( b ), and the 
piece b is upset and scarfed on one end, as in the comer plate. 



Fig. IS (h) 


When both pieces have been prepared, they are heated, fluxed, 
and welded, as described in the construction of the corner plate. 


29. Making- a Band Ring. —In making a band ring, like 
the one shown in Fig. 19 (a), a piece of f"Xlf" iron, 12 inches 
long, is upset at both ends. The ends are scarfed on opposite 



'h) 

Fig. 19 


sides, as shown at a and b, view (6), and the iron is bent into 
the form of the desired ring. To do this, the iron is heated and 


























































































































16 


HAND FORGING 


50 


then laid across the horn of the anvil and projecting beyond it. 
The projecting end is hammered and bent around, as shown 



(b) 





in (c), until the scarfed faces are in position for welding, but 
about f inch apart. The ends are next heated and fluxed, and 








































50 


HAND FORGING 


17 


then raised to a welding heat. To weld the ring, it is brought 
to the anvil and slipped over the horn, with the scarfed ends 
on the upper side of the horn. A few rapid blows with the 
hammer will make the weld, after which the ring is trued up 
so as to make it round and to make the iron of the required 
width and thickness throughout. This is done over the horn 
of the anvil. 

30. Making* a Ring Hook. —A ring hook of the form 
shown in Fig. 20 (a) may be scarf-welded. Its construction 
also shows a method of splitting stock for branch pieces that is 
valuable in smithing operations. On a piece of iron of good 
quality, such as Norway iron, J inch square and 5 inches long, 




a length of 2 inches is marked off from one end with a center 
punch and this piece is drawn out to 5 inches, leaving the stock 
of the form shown in (b). Next, a hole a, view (c), is made 
with a punch, the stock split out to the end, and the branches 
bent apart, as shown. The shank is then placed in a heading 
tool and the branches bent out, as illustrated in (d). During 
this part of the work, great care must be taken to prevent cracks 
from starting in the comers, as shown at b. When the iron 
has closed around cracks started in this way the piece is liable 
to be dangerously weak where they occur. They may be 
avoided by removing the piece from the heading tool when the 
branches have been partially bent out, placing it over the 
round corner of the anvil, and using a large fuller or a set ham¬ 
mer, as indicated in (e). The branches are drawn out to the 

205—8 








18 


HAND FORGING 


50 


proper dimensions, scarfed, bent to the ring form, and welded as 
in the case of the band ring. The piece is held in the tongs 

by the ring while the hook is 
being shaped. The finished 
piece should be sound, show 
no scarf or weld marks, and 
agree with the dimensions on 
the drawing. 

31. Making a Flat Ring. 

In making a flat ring, as shown 
in Fig. 21 (a), a piece of f" 
X1 J" flat iron 14 inches long 
is cut off and heated, and the 
end farthest from the tongs is 
bent edgewise over the horn of 
the anvil. As the circumfer¬ 
ence of the outside circle a a a 
of the ring is considerably 
greater than the circumference 
of the inner circle bbb, the iron will be upset along the inner 
edge and stretched along the outer edge by the bending. This 
will make the iron thicker than § inch at the inner edge and thin¬ 
ner along the outer; the iron will also buckle and twist when being 
bent. By hammering it flat on the anvil, using the flatter if 
desired, the iron can be brought back to an even thickness; how¬ 
ever, it should not be allowed to get far out of size, and its width 
and thickness should be frequently tried with the calipers. When 
bent, the iron will have the form shown in ( b ); the comers are then 
cut off, as indicated by the dotted lines d d, the ends scarfed and 
the iron bent on the anvil, as shown in 
Fig. 22, until the scarfs overlap, their 
inner surfaces remaining about J inch 
apart, as illustrated in Fig. 23. The 
heat is then raised, the weld made, and 
the ring finished with the hammer. 

32. Making a Chain. —A chain like that shown in Fig. 24 
is made from J-inch round iron that is cut into suitable lengths, 










































HAND FORGING 


19 


§50 


bent, scarfed, and welded into links that are afterwards joined. 
Each oblong link is made from a piece of stock 3J inches 
long. This piece is bent at the middle, over the horn of the anvil 



or around a pin of suitable size, bringing the ends parallel and 
of the same length. These ends are next scarfed, one on one 
side and the other on the opposite side, so that, when the ends 
are bent inwards, the scarfs face each other. These ends, after 
being bent so that the scarfs overlap, are brought to a welding 
heat, fluxed, and welded on the face of the anvil. The ring is 
finished on the horn. The weld is usually the thickest part of 
the link and is at the point where the wear is greatest. In 
making a long chain, two separate links are made and welded, 
and a third link is used to join them, forming a section of three 
links. Two such sections are slipped on a split link and the 
latter is closed and welded, thus joining the sections. This 
operation is repeated until a chain of the desired length is 
obtained 

33. Making a Pair of Tongs. —To make a pair of black¬ 
smith’s tongs for holding flat iron, such as is shown in Fig. 25, 
a bar of f-inch square iron, not more than 2 feet long, is marked 
at 2 inches from the end and heated. When hot, the marked 
end is flattened to a thickness of inch, leaving the shoulder, 



as shown at a, Fig. 26 (a), on one side. This may be done by 
holding the iron so that the marked edge is on the edge of the 
anvil and by flattening the end with the hammer. The piece is 

















































20 


HAND FORGING 


50 


again heated and placed on the anvil, as in ( b ), and flattened 
for about 3 inches in length. It is then cut from the bar and 
the other end c g of the piece is offset, as shown at c, view (c), 
and flattened for about 3 inches in length. The end g d is then 
drawn down to f inch round, as shown. The end d may be 
left a little larger than f inch, and then scarfed for welding. A 
duplicate piece is then made and a f-inch round rod 12 inches 
long is welded to each to form the handles. A f-inch hole is 
then punched through one of the pieces, as shown at b , view ( d ). 
The two parts of the tongs are now held together and the hole 
marked in the second piece by punching it through the 
hole already made. The first piece is then laid aside and 
the hole punched through the other one. 



Fig. 26 

34. The pin or rivet, shown in Fig. 26 (e), that is to hold 
the two parts together, is made by upsetting a f-inch rod at one 
end and forming it into a head. It is then cut from the bar, 
making it the proper length, and tried in the tongs to make 
sure that it fits. It is then put into the fire and heated on the 
end p. When hot the finished head h is cooled by being dipped 
in water, but the end p is left hot. The pin is then replaced 
in the fire and heated on the end. When hot, it is put through 
the two holes and the tongs finished by riveting the end of the 
pin. It frequently happens that the rivet bends in the holes; 
this makes the tongs tight, but the jaws will not stay parallel. 
In such a case the rivet must be driven out while it is still hot 
and another one made. 




































50 


HAND FORGING 


21 


35. The fuller may be used to good advantage in making 
the tongs. The bar having been cut down part way with the 
hot cutter, the material may be worked out to approximately 
the correct form with the fuller. Sometimes, it is well to take 
a heat over the work; that is, to go over the piece, when it is at 
a white heat, with a light hand hammer. In this way, the fibers 
that have become separated are rewelded and the forging 
improved. Since the weakest places of the tongs are at tne 
offsets and comers, the largest possible fillets should be at these 
points. The fillets may prevent the tongs from working easily; 
but if the tongs are heated to a red heat after riveting and are 
worked back and forth, the joints will usually loosen. The 
flat space around the rivet hole should be as large as possible, to 
increase the strength of the tongs. 



Fig. 27 


In making tongs, the parts should be inspected very closely 
before putting them together. A good way to detect flaws 
and defects is to heat the suspected part to a dull red; this 
will show all defects, such as cracks, seams, poor welds, etc., 
which often occur in the welds, angles, offsets in the jaws, and 
the metal near the punched holes. If the defects cannot be 
remedied, a new part must be made. 

36. Welding a Spring. —Great care is necessary in weld¬ 
ing a spring, because the steel beyond the weld is apt to be 
overheated, causing the spring to break later at that point. 
Different forms of welds are used, with equal success, though 
some are more difficult to make than others. A common way 
of welding a spring is shown in Fig. 27. Each end is split into 
three tongues and the middle tongue is bent away from the two 
outer ones, so that, when the two pieces are brought together, 






































0‘> 


HAND FORGING 


50 


they will fit, as shown in the illustration. As the scarfs in this 
weld are long and thin, the welding must be done rapidly, or 
the anvil will cool the pieces and cause a poor weld. The long 
lap of the scarfs is a disadvantage, as greater care is required 
to insure good results. If desired, the scarf weld shown in 
Fig. 11 may be used for joining springs. Each piece is upset 
and then scarfed, after which the pieces are put in the fire with 
the scarfs facing upwards. As soon as the flux melts and adheres 
to the scarfed faces, they are turned over and the ends are 
brought to a welding heat. The weld should be made at one 

heat, as there is danger 


of overheating the parts 
on each side of the weld 
while getting a second 
heat on the upset part. It 
is a good plan to roughen 
the scarfs, so as to prevent 
them from slipping. 






7 


(C) 

Fig. 28 


37. Welding Angle 
Iron. — Two pieces of 
angle iron may be welded 
together, end to end, by 
using the scarf weld. The 
ends are scarfed in the 
usual way, without up¬ 
setting, and the heel or 
comer of the angle is welded first. The welding of the 
sides is then completed, though it is the more difficult part of 
the operation, as the sides frequently do not weld perfectly. 
A better way of doing this work is to cut away a piece from 
corresponding sides, as shown in Fig. 28 (a), leaving the ends a 
and b projecting. These are now scarfed on opposite sides, 
heated, fluxed, and welded. The pieces will then be joined, as 
in ( b ), with a gap between the ends c and d. These ends are 
scarfed, and a piece of metal e, shown in (c), of the same width 
and thickness as the angle iron, is scarfed to correspond and is 
welded in place between the ends c and d. 





















§50 


HAND FORGING 


23 


WORK INVOLVING BUTT WELDS 

38. Knuckle-Joint Strap. —To make a knuckle-joint 
strap, shown in Fig. 29 (a), a short bar of stock is taken, slightly 
wider than one-half the width a of the strap, and of the thick¬ 
ness shown at b. The notch c, view ( b ), is made with the fuller 
and the end of the bar drawn to the form shown by the dotted 
lines. Next, this end of the bar is cut off at such a place as will 
give the piece shown in (c), and the face hollowed as shown 
at d. A second piece of the same form is then made, except 
that the face d is convex instead of concave. There will now 
be two pieces, as shown in (d), to be welded together, the 



excess of width having been given, that they might upset 
slightly at / during this operation. 

39. To weld them together, the two pieces are heated at 
the same time. When at a welding heat, the pieces are placed 
on the anvil in the relative positions shown in Fig. 29 (d), and 
the weld made with light blows of sledge hammers; or, they 
may be placed between the dies of a power hammer and welded 
with light blows, care being taken that the blows do not draw 
the sides too close to each other. Too heavy blows are liable, 
also, to spread the edges of the weld and weaken it. The 



























































24 


HAND FORGING 


50 


piece should be turned on its side, after the faces are welded, 
and the sides closed before the welding heat is lost. It must 
be remembered that the weld is due to the fluid condition of 
the metal at the surfaces that are joined, and the blows delivered 
should have only force enough to bring the surfaces entirely 
together. After the weld is made, the grooves shown in ( e ) are 
made with the fuller, and the end drawn out as illustrated by 
the dotted lines. The end is then cut to the curved form 
shown in (a) by the use of a hot cutter, and this end finished 
on the anvil. 


MISCELLANEOUS EXAMPLES OF WELDING 

40. Welding On Bolt Heads and Collars. —A ring may 
be welded to the end of a rod to form a head, or to the middle 
of a rod to form a collar. The welding operation in each case 
is the same. The first step is to bend the ring to shape and size 
from a piece of round or square stock. The ring thus made 

should not be welded but should be a 
split ring; that is, its ends should be 
about inch apart and the inside 
diameter should be just great enough 
to enable the ring to be slipped over 
the rod to which it is to be welded. 
The rod is first heated to a red heat; 
then the split ring is placed in the fire 
and both the ring and the rod are 
brought to a welding heat. When 
they have been withdrawn from the 
fire, the rod is quickly thrust into the 
ring and the first blow of the hammer 
is struck so as to close the gap in the 
ring, which is thus drawn tightly around 
the rod and can be welded firmly in 
place. Bolt heads made in this way are usually larger than 
the standard sizes formed by the upsetting operation. 

41. Crucible Tongs. —The jaws of a pair of tongs for 
lifting crucibles are shown in Fig. 30 (a). It would be possible 























































50 


HAND FORGING 


25 


to make the jaws by welding the fingers a to the arms b\ but as 
the tongs are subjected to a high temperature when handling 
crucibles, there is danger that a weld will be weakened and 
fail. It is better, therefore, to forge the arm and its fingers 
from one piece. Both jaws may be made from a piece of flat 
stock like that shown in (6). The sides are nicked deeply, at 
such a distance from the ends that the end parts a will be of 
the proper width to form the claws or fingers of the tongs. 
The central part b is then drawn down by hammering to the size 
of the arms of the jaws, after which it is cut in two at the 
middle. Each piece is then bent to form one jaw. 


42. Ladle Shank. —In the foundry, ladles are lifted and 
carried by ladle shanks. A ladle shank consists of a circular 



ring in which the ladle fits, and to which are welded handles 
by means of which the whole may be carried and tilted. The 
supporting ring is made in two parts a and b, Fig. 31 (a), that 
are afterwards welded together. Each part is formed from a 
piece of flat stock like that shown in (b). A hole c is punched 
through the stock, and the piece is split, as at d, to one side of 
the center line. The work is then bent and drawn to the shape of 
the piece a, view (a). The reason for splitting the stock off the 
center line is to make the arms of the piece a unequal. If they were 
made of the same length, the welds would come at the points e 
and /, where the bending strain is greatest, instead of at g and h. 
The piece b is made in the same way as the piece a, and the ends 
of the forks are scarfed as shown at g and h. They are clamped 


























26 


HAND FORGING 


§50 


and drilled so that iron rivets i can be put through to hold the* 
pieces in their correct relative positions during welding. The 
parts at g and h are then heated and welded, after which the 
handles j and k are attached by cleft welds. 



(a) 



(b> 



rr- 


43. Open-End Wrench. —There are several ways of 
forging an open-end wrench. One method is to split a piece 
of flat stock as shown in Fig. 32 (a), spread the fork, and bring 
it to the shape shown in ( b ). The ends a are next folded in 

toward the center b, 
on the same side, as 
shown by the dotted 
lines, and are welded 
down, thus forming a 
thick, heavy end that 
is still T-shaped. The 
branches are next bent 
over as in (c), to form 
the jaws of the wrench, 
and the inside faces 
are squared by filing, 
to fit the nut for which 
the wrench is intended. 
Another method of 
making an open-end 
wrench is shown in Fig. 33. A piece of flat stock of the required 
thickness is heated and fullered near the ends as shown in (a). 
The central part is drawn out to the size and length of the 
handle, as in ( b ), and the ends are forged to a T shape, as shown 
in ( c ). The branches of each T are next bent over, as in ( d ), to 
form the jaws of the wrench. One branch should be drawn 
around farther than the other, so that, when the opening is 
squared, as in ( e ), it will stand at an angle to the center line of 
the handle. The wrench illustrated is double-ended, but the 
same method may be used in making a single-ended wrench. 



44. Rocker-Arm From One Piece. —To make a rocker- 
arm from one piece, round stock is taken that is large enough 
in diameter to give, when flattened, the dimension a, Fig. 34 (a), 



















50 


HAND FORGING 


27 


and drawn to the form shown in ( b ). This will require great 
care, for there is danger that the dimension c may be made 
too great, or, if this is right, that the dimension b may be too 
small. Enough of one end is flattened to form the arm, and 
drawn to the form shown in (c). The dimension d is made 
to correspond to d in view (a). This piece is flattened with 
the hammer, the side to¬ 
ward which the stock is 
drawn being made as true 
and flat as possible from 
the shoulder to the end, 
and the recess at d formed 
by the use of the fuller. 

This leaves the stock / on 
the end, from which to 
form the boss. Next, the 
piece is clamped firmly 
near one shoulder and the 
flattened portion bent 
down, making the whole 
piece of the form shown in 
(d), by clamping the piece 
between the hammer dies 
and driving down the arm 
with sledge hammers. The 
boss is rounded as shown 
at g, view (e), by first 
shaping it to the form 
shown by the dotted lines 
at g, view (d), and then rounding it to form the boss. The 
portion outside the shoulder on the other end of the piece is 
treated in the same manner, or both ends may be flattened 
and notched first, and then bent. Rocker-arms are also forged 
by welding both arms to the shaft. 

45. Rocker-Arm With Welded Shoulder. —When it is 
not considered desirable to use stock that is large enough to 
form a shoulder of the required size, the shoulder should be 





-V_/ 


_ r\ 

(a) 



^ y 1 






r > 


























28 


HAND FORGING 


50 


made in the manner indicated in Fig. 34 (/). The rocker-arm 
is made from the stock at hand, leaving it too small at the 
shoulders and on the arms near the shoulders. A separate 
piece of stock is drawn to the form shown at i, and bent to fit 
closely around the shoulder that has been formed, as shown 
by the dotted lines. A welding heat is then taken on one 





shoulder, and that side is welded; this operation is repeated on 
the other side. After both shoulders have been treated in this 
way, the whole piece is gone over carefully and dressed to shape. 

46. Locomotive Reverse Shaft. —The method of forging 
a locomotive reverse shaft varies in different shops, but a good 
way of doing it is shown in Figs. 35 and 36. The shaft is first 
heated at a, where one of the arms is to be welded, and enlarged 
by upsetting, which is accomplished by swinging a heavy 


































































50 


HAND FORGING 


29 


suspended steel ram b, Fig. 37, against its end, the shaft being 
supported in a special fixture or anvil c, Fig. 35, made for the 
purpose. Similar heats are taken at other points where arms 
are to be welded. The arms are previously forged, usually 
under a drop hammer. The end of each arm is split, and each 
end is drawn out, as shown at e and /, Fig. 36 ( b ). View (c) also 
illustrates some of the details of the form of the arms and shaft 
before welding. The small arm a, view (a), is first welded to the 
shaft, after which one of the link-supporting arms d is welded on. 



47. The shaft is heated in one fire and the end of the arm 
in another; when they are both at the proper heat, they are 
brought out, the shaft is dropped into the crotch of the special 
support c, Fig. 37, and the arm placed on it. A few sharp blows 
on the upper end of the arm commence the weld at the center, 
and blows at e and /, Fig. 36 (b), complete it, a swage being 
used to finish the fillets about the end of the arm. The other 
arm h, view (a), is then welded on in the same way. The long 
arm g on the end of the shaft is sometimes made by first welding 
on a short piece, after which the shaft is taken to the machine 











































































30 


HAND FORGING 


50 


shop, machined, then returned to the smith shop, and the 
remainder of this long arm welded on, thus overcoming the 
difficulty of turning the shaft in the lathe with the long arm on it. 


48. During the welding the weight of the shaft is partly 
supported by the chain i, Fig. 35, hanging from a chain block 
on a swinging crane. The shaft is handled by the fixture /, 



(a) 



which is fastened to it by means of a clamp k provided with 
a gib and key. The end of the clamp k has a thread and nut 
for the purpose of attaching weights to counterbalance the 
arms d and h t Fig. 36. The main forge is at l, Fig. 37. The 
forge in which the arms are heated is located at m. A cast- 
iron plate n, about 4 feet by feet in size, planed on the top 
and the edges, strongly ribbed on the bottom, and provided at 
one side with a pair of centers, adjustable lengthwise in a groove, 
is used to test the straightness of the shaft. There is a space 
of 3 or 4 feet between the fixture c and the plate n. 
















































50 


HAND FORGING 


31 


49. Locomotive Valve Yoke. —Of the several methods 
of making a locomotive valve yoke, one of the best is to use 
a piece of square hammered iron, as indicated by the dotted 
lines in Fig. 38, and draw one end as shown at a. The other 
end is split, opened out, and each end drawn out as shown 
at b and c, after which the two ends are split and bent down 
as illustrated at d and e. Another piece of iron is prepared 



Fig. 37 


of the proper size and length and bent as at /, with its ends 
properly scarfed for welding. First one side is welded and then 
the other, when it only remains to give the yoke the necessary 
finish. The clamp g is used to hold the parts in place while 
making the first weld at e. 

50. Wrouglit-Iron Rudder Frame. —Many rudder 
frames of late years have been cast in open-hearth steel, in one 




























































32 


HAND FORGING 


50 




C\ 




e s 

k 


piece; but owing to the possibility of hidden blowholes, or 
invisible cracks in the comers, a wrought-iron frame is some¬ 
times preferred. Fig. 39 shows such a frame in which it was 

necessary to make 
nineteen welds, the 
location and order of 
which are shown by 
the figures, the dotted 
lines indicating the 
character of each weld. 
Number 19 was made 
by welding in a dia¬ 
mond-shaped piece, 
or glut, which has the 
fiber of the iron lengthwise in the finished work. 

The main piece a in this case is 23 feet long. Eight inches of 
the upper end is square, below which it is turned 9 inches in 
diameter for a length of 6 feet. A pivot c is also turned at the 
lower end. The part of the frame d to which the arms are 
welded is square on that side and half round on the back, as 
shown in section at e. The arms, where they are joined to d, 
are from 3 to 4 inches by 9} inches. At the outer end / they 
are 3 inches by 9f inches, and the part of the frame at g is the 
same size. 




Fig. 38 



51. Most of the welds are V-shaped, or cleft welds, but 
occasionally a double-cleft weld is used, into which a diamond¬ 
shaped piece is welded, in order to obtain the correct dimen¬ 
sions. Most of the welding is done without taking the frame 



















































50 


HAND FORGING 


33 


out of the fire. The frame, laid on a flat-topped forge, is 
temporarily enclosed in firebricks at the point to be welded; 
the fire is then built under and around the point, the top of the 
brickwork being covered with several sections made up of an 
iron frame filled with firebricks and provided with a bail, or 
eyebolt, for lifting the section to replenish the fuel or remove 
the work. Sometimes a chain fitted with a tumbuckle is so 
arranged on either side of the frame as to enable the parts that 
are to be welded to be drawn together. 

52. Two steel ramming bars are provided, each about 
9 feet long and If inches in diameter, except at the working 
end, where they are 2\ inches in diameter and slightly rounded. 
When the welding heat is reached, the tumbuckles are quickly 
tightened, the ramming bars introduced through either end of 
the furnace, and the scarf of the weld vigorously pounded down. 
The top covers of the furnace are then removed and three men 
with sledges finish the upper edge of the weld. The piece is 
then lifted from the fire and placed on the anvil and the entire 
weld gone over with sledges, three men striking at the rate of 
about 36 blows each, or 108 blows a minute, on the work. Care 
is usually taken to have a little surplus stock at the weld, which 
is then trimmed off with a hot cutter. 

53. Welding Pipe. —An open fire with an overhead hood 
is well adapted to pipe welding, which may be done in a forge 
fire in several ways. In the case of extra heavy iron or mild- 
steel pipe welded together in lengths varying from two pipe 
lengths to 300 or 400 feet, as used for refrigerator coils and 
sometimes for steam coils for heating liquids, the pipe may be 
prepared by reaming it out at one end to a taper of about 60°, 
the other end being given an outside taper to match. This 
operation can be done on a turret machine or, with suitable 
dies, on a bolt cutter. Long lengths of pipe, while being heated, 
are usually supported by a wooden trough or box. The ends of 
the pieces of pipe, with inside and outside taper, are placed in 
the fire and brought to a welding heat, using a little sand or 
other flux if required. The ends of the pipe are brought 
together in the fire, and two or three sharp blows are given on 


205—9 


34 


HAND FORGING 


§50 


the cold end of one pipe by the helper, the smith meantime 
holding the other pipe. The weld is started by the blows on 
the end of the pipe, which is quickly drawn through the fire, 
bringing the weld into a bottom swage or on to an anvil located 
near the fire and directly under the pipe. The blacksmith 
applies a top swage, while the helper strikes light quick blows 
on the swage with a very light sledge hammer, the blacksmith 
turning the pipe meanwhile. The welding must be very quickly 
done, as pipe cools more quickly than solid iron. A few passes 
of a coarse file will remove the scale, and the pipe is then moved 
endwise in the trough for the next weld. 

54. Welding Bar Iron to Pipe. —To give lightness, the 
handles of long tools are often made of pipe, which is welded 
on. An example of this class of tools is the slice bar used by 
the fireman of a stationary boiler to clean the fire. The solid 
iron or steel end of the tool is upset at its shank, and the pipe 
that is to form the handle is split for a distance of 3 or 4 inches 
from the end. The solid shank is first placed in the fire and well 
heated. Then the split end of the pipe is put in, so that both 
pieces will reach a welding heat at the same time. The shank 
is inserted in the split end of the pipe and the two are driven 
together before being removed from the fire. The weld is 
closed and finished on a bottom swage. 

55. Welding Boiler Tubes. —The ends of boiler tubes 
often give out while the main parts are still in good condition. 
To avoid the expense of wholly new tubes, new ends are welded 
on the old tubes. The worn-out ends are first cut off squarely 
and the ends of the remainder of the old tube are given a slight 
taper. Pieces of new tube, known as safe ends, are cut slightly 
longer than the old pieces that were cut off. Each safe end is 
scarfed at one end, over the horn of the anvil, and is thus 
flared enough to allow the tapered end of the old tube to enter 
it. The ends of the safe end and of the old tube are placed 
in the fire and brought to a red heat. The safe end is then 
withdrawn and set on the anvil with the flared end up and the 
helper drops the tapered end of the old tube in, jarring it down 
until the two overlap ^ or § inch. The smith immediately 




50 


HAND FORGING 


35 


closes the joint all around by hammering down the scarf with 
a light hammer. The closing should be done quickly, as a tube 
loses its heat much more rapidly than does a solid bar. 

56. After the scarf has been closed down, so that no dirt 
can get into the joint, the piece is replaced in the fire and 
brought to a welding heat. A mandrel of suitable size is then 
inserted into the safe end and the weld is hammered down 
and finished by using top and bottom swages. The swages 
should have chamfered edges, so that the tube will not be caught 
and pinched. 

The safe end and the old tube may be joined in the fire 
before the final welding. In that case, both are brought to a 
welding heat, as before, and the tapered end is inserted into the 
safe end. The helper strikes the safe end and drives it over the 
old tube, at the same time keeping it in line with the tube. 
The smith, using a light hammer with an iron handle, welds the 
scarf all around, while the pieces are still in the fire. The final 
hammering and completion of the weld are done as before, with 
mandrel and swages. 



Serial 1688 


TOOL DRESSING 


Edition 1 


TOOL STEELS 


METHOD OF MANUFACTURE 

1. High-carbon steels and high-speed steels are known 
as tool steels. The liigli-carbon steels are compounds of 
iron and carbon, containing from .60 to 1.50 per cent, of carbon. 
They differ from one another principally in the amount of 
carbon they contain, and their most valuable property is that, 
by proper heat treatment, they may be made very hard. The 
high-speed steels contain, in addition to the iron and carbon, 
one or more of the following metals: chromium, tungsten, 
molybdenum, and vanadium. These steels possess an 
advantage over the high-carbon steels in that tools made of 
them will cut at much higher speeds than is possible with tools 
made of carbon steels, as high-speed steels have the property, 
known as red hardness, of retaining their hardness when 
heated to a red heat. 

2. The best grade of tool steel is made by what is known 
as the crucible process, and is called crucible steel. Crucible 
steel, also called cast steel, is made by melting a com¬ 
bination of suitable materials in a crucible, and then casting 
the charge into an ingot that is reheated and rolled into bars. 
One method of making crucible steel is to pack wrought iron, 
which may be broken into small pieces, and some material that 
contains the desired amount of carbon into crucibles, and then 
melt it. These crucibles are about 2 feet high and 10 inches in 

COPYRIGHTED BY INTERNATIONAL TEXTBOOK COMPANY ALL RIGHTS RESERVED 

§51 




2 


TOOL DRESSING 


§51 


diameter and are capable of withstanding very high temper¬ 
atures. The melting furnaces are of various forms, but all are 
either' lined with or made entirely of refractory material. 
These furnaces are frequently rectangular in form, and large 
enough to hold two crucibles with the necessary fuel for melting 
their charges. They are arranged side by side in a row and 
connected with a common flue; their tops are usually on a level 
with the floor, while the ash-pits are reached from a pit extend¬ 
ing along the front of the row. 

3. Sometimes manganese and material for a flux are added 
to the charge in the crucibles, after which the crucibles are 
carefully covered with air-tight lids made of the same material 
as the crucibles. After the charge is fused, it is cast into an 
ingot, which is more uniform in structure than the wrought 
iron from which it was made. This ingot is reheated and worked 
under the hammer, then rolled or hammered into bars and 
placed on the market; this working greatly improves the quality 
of the metal. 

The product of this method of working was the first to be 
called crucible or cast steel, but now the term is applied also 
to the product obtained by fusing together in sealed crucibles 
wrought iron and carbon, to which there are added tungsten, 
chromium, molybdenum, or vanadium, and a flux, and casting 
them into an ingot that is treated in the same manner as that 
just described. 

4. The material called cast steel, the use of the term being 
herein confined to crucible tool steel, must be carefully dis¬ 
tinguished from the material represented by the term steel 
casting. The latter term denotes a material made by a dif¬ 
ferent process and is altogether different from cast steel. 

Many of the modern furnaces are fired by gas or crude oil. 
The contents of the crucibles are sometimes poured into a 
large ladle, which mixes the charge and insures a more uniform 
grade of steel. The contents of this large ladle are then poured 
into ingot molds and these ingots are subsequently worked 
down under hammers or with rolls. The best tool steel is 
worked down entirely under hammers. 


§51 


TOOL DRESSING 


3 


TEMPER AND TREATMENT OF TOOL STEEL 


TEMPER 

5. The steel maker uses the word temper to indicate the 
amount of carbon in the steel; thus, steel of high temper is 
steel containing a high percentage of carbon; steel of low 
temper is steel containing little carbon; steel containing amounts 
of carbon between these is said to be of medium temper. This 
term should not be confused with the act of tempering, which 
is an operation for reducing the hardness of steel to such a 
degree as to adapt it for doing the particular kind of work 
required. The temper of steel is often indicated by saying 
that it has a certain number of points of carbon, a point 
being .01 per cent.; thus, when it is said that a piece of steel 
contains ten points of carbon, it has ten one-hundredths per 
cent., or one-tenth of 1 per cent., of carbon, which is usually 
written .10 carbon, and the steel is known as point 10 carbon 
steel, or 10 point carbon steel. A .10 carbon steel may also be 
indicated thus, .1 per cent, carbon steel. 

6. Seebohm gives the following list of useful tempers for 
tool steel: 

Razor temper, 1.5 carbon. Steel of this temper requires 
very skilful manipulation, as it is easily burned by being over¬ 
heated; when used for turning chilled rolls, it will do much 
more work than ordinary tool steel. 

Saw-file temper, lfiO carbon. Steel of this temper requires 
very careful treatment; although it will stand a higher degree 
of heat than the preceding temper, it should not be heated 
beyond a cherry red. 

Tool temper, 1.25 carbon. Steel of this temper is most useful 
for drills and lathe and planer tools when they are to be used 
by the average workman; by careful and skilful manipulation, 
it is possible to weld steel of this temper. 

Spindle temper, 1.10 carbon. Steel of this temper is good 
for very large turning tools, circular cutters, mill picks, taps, 
screw-thread dies, and the like; it requires much care in welding. 



4 


TOOL DRESSING 


51 


Chisel temper , 1.00 carbon. Steel of this temper is very 
useful for a great variety of tools. It welds easily, is tough 
when unhardened, and may be hardened at a low heat; it is 
well adapted for tools that must have a hard cutting edge 
backed by unhardened metal that will transmit the blow of the 
hammer without breaking, as in cold chisels. 

Set temper , .80 carbon. Steel of this temper is well adapted 
for tools, such as cold sets, having an unhardened part that 
must hold up under the severe blows of a hammer; it may 
easily be welded by a smith accustomed to working tool steel. 

Die temper , .75 carbon. Steel of this temper is suitable for 
tools that must have a hardened surface and be able to with¬ 
stand great pressure, as dies for drop hammers, or for pressing 
or cupping sheet metal into boiler heads and allied forms; it is 
easily welded. 

7. The percentages of carbon in the steels suitable for dif¬ 
ferent classes of work under average conditions are as follows: 

.50 carbon for hot work, battering tools, hammers, etc. 

.60 to .70 carbon for dull-edged tools. 

.70 to .80 carbon for cold sets and hand chisels. 

.80 to 1.00 carbon for chisels,.drills, dies, axes, knives, etc. 

1.00 to 1.20 carbon for axes, knives, large lathe tools, large 
drills, and dies. If used for drills and dies, great care is required 
in tempering. 

1.20 to 1.70 carbon for lathe tools, small drills, etc. 

.90 to 1.00 carbon is the best steel for general work. 


TREATMENT OF TOOL STEEL 

8. Distinguishing Iron and Steel. —The smith is often 
called on to pick out a piece of a certain kind of steel from a pile 
containing iron, low-carbon steel, high-carbon steel, and special 
steels. Formerly, the only test was to pick up a piece and 
strike it with a hammer; if it sounded dead it was wrought 
iron, if it rang it was steel. This did very well when only one 
grade of steel was used in a given establishment, but now, when 
many grades are used, it is much more difficult. Some of the 



51 


TOOL DRESSING 


5 


low-carbon steels will sound dead under the hammer, but they 
can usually be separated from a lot of wrought-iron bars, as 
the surface of the latter is generally very much rougher than 
that of steel bars. Then, too, breaking a small piece from the 
end of a bar will show the difference between steel and iron, 
steel having a crystalline appearance, while the fracture of the 
iron presents a fibrous appearance. The emery-wheel test, 
however, is said to be the best for distinguishing different 
grades of steel. Hardened carbon steels give off bright daz¬ 
zling sparks when ground on an emery wheel; the harder the 
steel, the brighter the sparks. Alloy steels and wrought iron 
give off dull red sparks. 

9, Breaking Off Carbon Steel. —Carbon steel is gener¬ 
ally broken by nicking it, placing the nicked edge over the 
edge of the anvil and striking the projecting end. Sometimes 
the end of a light bar is passed through the hardie hole or the 
pritchel hole until the nick is in line with the top of the anvil; 
the bar is then broken by jerking it quickly to one side. Another 
method for breaking off pieces of tool steel, such as those used 
for cold chisels, lathe tools, etc., is to nick the bar cold at the 
required distance from the end and pass the bar through a hole 
in a swage block until the nick comes opposite the edge of the 
block; the projecting end should then be struck a sharp blow 
with the hammer. This will break off the piece without sting¬ 
ing the hand supporting the end of the bar, and prevent the 
piece from flying across the shop. Carbon steel may also be 
severed from the bar by cutting it while hot or by sawing. 

10. Cutting Off High-Speed Steel. —When high-speed 
steel is nicked and broken from the bar, the structure is usually 
injured. For this reason, high-speed steel should never be 
broken from the bar but should be severed from it by cutting. 
The circular cold saw and power hack saw are most commonly 
used for this purpose. The saws used to cut high-speed steel 
should themselves be made of high-speed steel. When a large 
amount of small stock is to be cut from the bar, the stock may 
be formed into bundles, and, by holding the bundles very 
rigidly, no difficulty will be experienced in cutting them. 


6 


TOOL DRESSING 


51 


11. Heat -Treating Operations .—The properties of steel, 
such as hardness, toughness, etc., may be modified by heat 
treatment, which consists of heating the steel to certain temper¬ 
atures and then cooling it in various ways. The usual heat 
treatments are annealing , hardening , and tempering. 

Annealing is a term applied to the operation of heating 
steel to about a cherry red and then permitting it to cool slowly, 
thereby causing it to become soft and of uniform structure 
throughout. 

Hardening is a term applied to the operation of heating 
steel to about a cherry red and then cooling it suddenly. The 
steel is usually cooled by plunging it in water. The degree 


El 

1 

■El. x ' \ 

|| PI.. w *' 

A 

A 

1 

4" . J, 

o" J 




2L®1 

illliiB.... K 

EP^'is . "■ 

ffl'lN 
_ i- 


Fig. 1 


of hardness depends on the amount of carbon in the steel, the 
temperature to which it is heated, and the suddenness with 
which it is chilled. 

For hardening, high-carbon tool steel should be heated to 
from 1,400° F. to 1,475° F., and never above 1,500° F. If 
high-speed steel is heated to 1,800° or 2,200° F. and cooled in 
a blast of air, or in warm oil, the steel will be hardened. 

Tempering is a term applied to the operation of reducing 
the hardness of steel to any desired degree. If a hardened 
piece of steel is slowly heated, it will gradually become softer 
as the temperature rises; when the desired reduction in hard¬ 
ness is obtained, any further softening of the steel can be pre¬ 
vented by dipping it into some cold liquid. The hardness of 
the steel after the tempering process is also known as its temper. 

12. Temper Colors. —The temper of hardened steel may 
be drawn by the aid of what are known as temper colors. 
Suppose the end a, Fig. 1. of the hardened wedge is laid on a 
piece of hot iron while the end c of the wedge is laid on a oiece 











































§51 


TOOL DRESSING 


7 


of cold iron. The large end a will rapidly become hot from 
its contact with the heated bar of iron, while the other end c 
will warm up very slowly. Soon it will be noticed that colors 
have begun to appear on the surface of the steel. A very pale 
yellow starts at the hot stock and creeps toward the small end, 
being followed by a darker yellow, then by a brown, and so 
on, until by the time the yellow is close to the small end, the 
large end is of a deep slate color. 

The colors produced in tempering steel tools are caused by 
the oxidation of the surface of the steel. The color varies with 
the temperature, and indicates the temperature to which the 
part has been heated. 

The colors in their regular order, beginning with that indi¬ 
cating the greatest hardness of the steel, are generally known 
by the following names: very pale yellow, pale yellow, light 
straw, full yellow or straw, dark straw, brown, brown with 
purple spots, purple, dark blue, full blue, light blue, and gray. 

13. Table I shows what colors are produced at various 
temperatures, and it also gives the names of a few tools or 
instruments usually tempered to the various degrees of hard¬ 
ness obtained at these temperatures. The temper should be 
drawn slowly, as it is then easier to watch changes of color 
and the danger of drawing it too far is reduced. Furthermore, 
when the temper is drawn slowly, the length of the part drawn 
to the desired color will be greater, which will permit the tool 
to be reground oftener before rehardening is necessary. Differ¬ 
ent makes of steel vary somewhat as to the degree of hardness 
corresponding to a given color, but the table may be taken as 
representing a fair average. 

By examining the gradations of color on the accompanying 
chart of Temper Colors and Approximate Temperatures 
through a narrow slot, say f inch by 1J inches, in a piece of 
white paper or cardboard, an approximately correct idea of 
the various temper colors given in Table I may be obtained. 
The opening in the cardboard should be placed opposite the 
name of the color to which the temper of the steel is to be 
drawn. It should be borne in mind, however, that the color 


TABLE I 


/ 


TEMPER COLORS AND CORRESPONDING} TEMPERATURES 

OF STEEL 


Color 

Temperature, in 
Degrees 
Fahrenheit 

Kind of Tool 

Very pale yellow 

430 

Scrapers, light-turning tool 
lancets 

Pale yellow 

450 

Razors, surgical instruments 


460 

Lathe tools, milling cutters 

Full yellow, or straw 

470 

Penknives, drills for iron 

Brown 

490 

Taps, reamers, dies for sere 
cutting, small cutlery, shear 
flat drills 

Brown with purple spots 

510 

Axes, planes, pocket knives 
wood chisels 

Purple 

530 

Twist drills, cold chisels for 
very light work, table knives, 
large shears 

Dark blue 

550 

Wood saws 

Full blue 

560 

Stone-cutting chisels, fine 
saws, daggers 


580 

Carving knives, springs 

Light blue 

600 

Drills for wood, cold chisels, 
swords 

Gray 

700 to 750 



8 



























































TEMPER COLORS AND APPROXIMATE TEMPERATURES 


A fiprox. 



Colors 


Gray 


Light blue 


Full blue 


Dark blue 


Purple 


Brown with purple spots 


Brown 


Dark straw color 


Full yellow, or straw color 


Light straw color 


450. Pale yellow 


430. Very pale yellow 













§51 


TOOL DRESSING 


9 


values of the chart are not in any sense fixed or absolute for 
different grades of tool steel exhibit different gradations of 
color when tempered. Practice in tempering any given grade 
of steel is therefore necessary in order to determine whether 
the degree of hardness corresponding to a given color on the 
chart is such as to enable different tools to meet the require¬ 
ments of the work for which they are intended. The chart 
will, however, serve as a guide in determining the characteristic 
qualities of various grades of steel. 

14, Working Tool Steel. —Tool steel must be carefully 
heated for working. The heating must be uniform, for, unless 
the metal is uniformly heated, violent stresses are liable to be 
set up in it which will cause cracking in hardening. If the 
steel is heated so that the outer parts are hotter than the center, 
the outer portion will be forged by the hammer blows while 
the inner portion will remain nearly in its original form. Forg¬ 
ing at too low a heat will injure the steel in the same manner 
as uneven heating. 

The steel should be heated thoroughly to make it plastic 
before working. The heat required varies, with the steel, 
from a cherry red to a bright yellow heat, or from about 1,400° 
to 1,600° F. The heat required for working any particular 
steel is usually specified by the steel maker or it may be deter¬ 
mined by trial. To avoid oxidizing the steel, when the heating 
is done with a solid fuel, the steel should be surrounded by 
plenty of fuel so that the air blast will not come in direct con¬ 
tact with it. 

A fire made of clean soft coal that has been well charred 
or coked is well suited to heating for working, but as steel 
absorbs sulphur readily and as sulphur is very injurious to 
steel, care must be taken either to use a fuel low in sulphur or 
to remove as much sulphur as possible by heating a heavy bar 
of iron in the fire for about 10 minutes. The iron will absorb 
most of the sulphur and the fire is then ready to heat the steel. 
Care should be taken not to let the steel lie in the fire and soak 
up heat after it has become hot enough to work, as soaking is 
injurious. Soaking consists in heating the steel so slowly .that 


10 


TOOL DRESSING 


51 


there is a loss of carbon from the surface of the steel, and as 
a result the surface becomes too soft. On the other hand, too 
rapid heating to too high a temperature results in overheating, 
or burning, the steel, and in unequal expansion in the piece, 
which may cause it to crack when being hardened. * 

15. After the steel has been properly heated it should be 
worked fast, using rapid hard blows and reducing it with one 
heat to as nearly as possible the size and shape wanted. If 
cracks or flaws appear, the steel has been overheated and should 
be discarded; if none appear, it has not been injured by the 
heating. If the piece has been formed to nearly the desired 
size by the first working, it need not be heated so hot for the 
second working. The finishing off of the comers, edges, and 
flat surfaces, and the bending and straightening may be done 
at a lower heat than that required for the first working. Gener¬ 
ally, a steel containing not more than 1.20 per cent, of carbon 
will stand a bright yellow heat for forging, and if it is desired to 
reduce it as much as one-half in size it should be brought to 
this heat. If it is then hammered promptly and thoroughly 
on first one side and then the other until it becomes dull red, 
the steel will be as tough and strong as it can be made by 
forging. If it is not well hammered it will be weak and coarse¬ 
grained. 

16. Welding Tool Steel. —Welding tool steel is a difficult 
operation and should be avoided where possible, especially if 
the steel is to be hardened subsequently. When two pieces 
of steel are heated for welding and are exposed to the air, they 
become covered with a scale of oxide of iron. To secure a 
perfect contact of the parts, this oxide must be made so fluid 
that it will readily squeeze out from between the surfaces to be 
welded. To do this, either the steel must be heated to the 
temperature at which the scale will melt, which will be a very 
high temperature, or some means must be used to fuse the 
scale at a temperature below that at which the steel would be 
injured. This is done by applying to the heated parts a flux 
that melts and adheres to the heated surfaces, preventing 
excessive oxidation and, at the same time, uniting with the 


§51 


TOOL DRESSING 


11 


scale to form a mixture that is fusible at a much lower temper¬ 
ature than would be necessary to melt the scale alone. Borax 
is commonly used for this purpose. 

Before attempting to weld any grade of steel, the smith 
should know its quality and how its structure and welding 
properties will probably be affected, if they are affected at all, 
by varying both the temperature to which it is heated and the 
method by which it is worked. This information is furnished 
by the steel maker or it may be obtained by tests made on 
specimen pieces. 

17. The structure of the steel, which means the size of the 
crystalline grains of which the steel is composed, is affected 
by the temperature to which it is heated, the amount and 
character of the subsequent working of the metal in making the 
weld, the heat of the metal when the forging work on it is 
discontinued, and the rapidity of the final cooling. Some steels 
will withstand a greater heat than others without injury, but, 
in general, the most important points to be observed are the 
methods of working and cooling the steel. It seems to be 
established that the greater the amount of carbon that a steel 
contains, the lower is the temperature to which it may safely 
be heated. If the steel is heated to a full red, or above, for 
welding, and the work of making the weld is done quickly, 
leaving the metal still at a high temperature, the metal, if 
allowed to cool slowly, will be coarser grained and more brittle 
than when the forging is continued until the temperature of 
the steel falls below that of a low red and the metal is allowed 
to cool slowly from that point. On the other hand, if, after 
having finished working, the steel is cooled suddenly to a low 
red heat by being plunged into water, and then allowed to cool 
slowly in a dry place, the quality of the grain and the strength 
of the piece will be superior to that which would result from 
allowing it to cool slowly from the higher temperature. 

18. If the piece is cooled suddenly from the temperature 
at which the work was finished to the temperature of the air, 
by quenching in water, the size of the grain and the strength 
of the steel will in all probability be superior to that obtained 


12 


TOOL DRESSING 


51 


by allowing the steel to cool slowly in the air. Cooling rapidly 
from a too high heat is, however, likely to crack or break the 
steel. 

With carbon steels, the tempering heat is lower than the 
annealing heat; the annealing heat is the same as the hardening 
heat; and the hardening heat is lower than the forging heat. 
The only exception is in the case of the high-speed alloy steel. 

In making a number of articles of steel, should a defect 
appear always in the same place, it is likely that something is 
wrong with the method rather than with the steel. 


EXAMPLES OF TOOL DRESSING 


CARBON-STEEL TOOLS 


CHISELS AND HAMMERS 

19. Making a Flat Cliisel. —If it is required to make 
a flat chisel of the form and dimensions illustrated in Fig. 2, a 
piece about 6 inches long is first cut from a bar of f-inch octagon 
steel. The piece is then put into the fire so as to heat the end, 
for a distance of about 2 inches, to a cherry-red color. The 



fire must be clean and the heat must be raised with sufficient 
rapidity to prevent soaking the steel, and yet heat the piece 
thoroughly without burning the corners. 

When a cherry-red heat is reached, the end of the piece is 
drawn to a wedge shape by rapid blows on a set hammer. 
If the end of the chisel is spread sidewise during the working, it 
is now brought back into shape by a few hammer blows on the 








































51 


TOOL DRESSING 


13 


edges; all the edgewise hammering should, however, be done 
early, and not when the heat is low. The end is then drawn 
to an edge a by light hammer blows, taking care not to work 
it below a black heat, as this would tend to crack it. When 
the edge has been drawn out, the rough or ragged part is cut 
off with the hot cutter, laying a piece of soft iron between it 
and the anvil so as to avoid cutting against the hardened face 
of the anvil and spoiling the hot cutter. The head of the 
chisel is then rounded, as shown at b. 

20. In most cases the piece should be annealed in order to 
make it homogeneous; although the annealing is often neglected, 
better results are obtained when it is done. When steel is 
worked, its structure changes, and in the case of the chisel, the 
thinner part—having been worked more than the thick part, 
and having been heated more rapidly to a higher temperature, 
and also having been cooled more quickly by the cold anvil 
and hammer—is more likely to be brittle and no longer uniform 
in structure. Its structure should be made uniform, however, 
before hardening; otherwise, the various parts are likely to be 
hardened and tempered unevenly. The process, of heating for 
hardening the tool does much to restore the uniformity of 
steel, but often this is not sufficient, and for this reason it is 
preferable to anneal every tool before it is hardened. To 
anneal the steel, it is put into the fire and heated to a red heat, 
care being taken not to overheat the thin edges. When uni¬ 
formly heated, it is taken from the fire and placed in the warm 
ashes on the side of the forge, and allowed to cool until the heat 
produces no visible color when the piece of steel is held in a 
dark place, as under the forge; and then it may be cooled by 
being plunged into water. This makes its structure uniform 
once more, and it is ready to be hardened. 

21. In order to harden the chisel, it is heated to an even 
red color, a little below the forging heat, allowing the point 
to extend a little beyond the hottest part of the fire. It is 
then plunged endwise into cold water, care being taken to 
plunge it in straight, letting the sharp end strike the water 
first. It should be thrust down vertically, then moved up and 


205—10 


14 


TOOL DRESSING 


ol 


down and turned around, in order to bring its surface in con¬ 
tact with as much cold water as possible, thereby cooling it 
rapidly. If plunged sidewise, one side will cool sooner than 
the other, and the piece will warp or crack. The warping 
would not be a very serious defect in a cold chisel, but it would 
be in finer tools, and carelessness in making rough tools might 
lead to carelessness in making finer ones. When plunged, the 
work should not be held quietly, because the hot tool transforms 
the water with which it comes in contact into steam, which 
envelops the steel and keeps off the cold water; by moving the 
piece continually it is chilled more effectively. Moving the 
steel from side to side, however, has the same effect as that 
of plunging it sidewise. The bath should be kept at a temper¬ 
ature of about 60° F. The water should be free from acid, 
soap, or grease, and, when possible, should be soft. 

22. When properly hardened, the faces of the chisel are 
rubbed bright with emery cloth or sandpaper, or a piece of 
grindstone, so that the colors can be watched while drawing 
the temper. If the body of the chisel is now heated slowly by 
holding it across a bar of hot iron, the temper will be drawn 
gradually, and when the brown color reaches the cutting edge, 
the chisel is dipped into water to hold the temper where it is. 
The chisel can then be ground on a grindstone and tried on a 
piece of iron. The point should be the hardest part of the 
chisel. 


23. In practice, a cold chisel is generally hardened and 
tempered in one heat. The cutting end is heated to a red color, 
letting the heat extend pretty far back, say about 3 inches. It 
is then taken from the fire and the point plunged into cold 
water about 2 inches. In plunging a piece of steel in this way, 
it must be moved up and down a little, so as to avoid starting 
a water crack between the hardened part and the soft stock. 
As soon as the point has been sufficiently chilled, it is polished 
quickly. The heat still retained in the stock will gradually run 
to the point and draw the temper, and the colors can be 
watched on the bright part. When the desired color is reached 
at the point, the chisel is dipped into cold water to hold the 


51 


TOOL DRESSING 


15 


temper where it is. Should the colors come too fast* after dip¬ 
ping, the chisel may be dipped a second time and the drawing 



Fig. 3 


operation repeated; while if they come too slow, their coming 
may be hastened by moving the point over the fire, taking care 
not to heat it too much. 

In dipping tools for hardening or tempering, great care 
must be taken to keep them in the water long enough to chill 
the steel throughout. When the tool is dipped, the outside 
becomes chilled and contracts, forming a hard, brittle shell for 
the heated interior mass of metal. As the latter cools it also 
contracts, but being held to the already hardened external 
shell it cannot contract to its original size, and hence there is 
produced an internal stress on the steel that may cause it to 
crack. To prevent cracking, the steel should not be plunged 
when heated beyond a red heat. 

24. Making a Cape Chisel. —Suppose a cape chisel of 
the form and dimensions shown in Fig. 3 is to be made. The 
heated end of the bar of steel is first laid across the rounding 
edge of the anvil, the end of the bar toward the hand being below 
the face of the anvil, as shown in Fig. 4. The first forming, 
which is begun at a distance from the end of the bar that will 
give sufficient metal for the chisel, is for the shoulders of the 
sides where they widen 
into the handle of the 
chisel. To form these 
shoulders, the fuller is 
used over the round¬ 
ing edge of the anvil, 
care being taken to 
have the shoulders equal and opposite each other. The piece 
is turned frequently, so that the effect of the work may be seen 









































































16 


TOOL DRESSING 


§51 


and the sides kept alike. After the shoulders have been formed, 
the stock on the sides may be drawn down slightly with the 
fuller and the sledge and hammer are used to bring the chisel, 
roughly, to the form shown in Fig. 3. The finishing is done 
with the use of a hand hammer or a flatter. When properly 
formed, the chisel is cut from the bar to the required length, 
which ranges between 6 and 8 inches, and the head is formed, 
after which the chisel is annealed. The point is then generally 
hardened and the temper drawn in a single heat, in the same 
manner as described in connection with the flat chisel. 

25. Making a Hammer. —For practice in working tool 
steel, the making of a cross-peen hammer, like that shown in 
Fig. 5, is useful. Two hammer heads may be made at one 



Fig. 5 


operation, by using a piece of tool steel f inch square and 
5f inches long. When the face end a of the hammer is drawn 
out to the form shown, the change in section from the square 
to the octagonal, and the slight taper from the eye to the face, 
will increase the length by \ inch, or more. As it is advisable 
to form the eyes before drawing out the ends of the hammers, 
the centers of the eyes are prick punched on each end of the 
stock. The distance of these centers from the ends of the stock 
is equal to If inches plus f inch (one-half the length of the eye), 
less \ inch (the amount the face end will be drawn out), or 
If inches. Having marked the centers If inches from each 
end, the holes for the handles are next punched with an eye 
punch that is considerably smaller than the required hole. 
The punch is first driven half way through from one side and 
then half way through from the other side. The holes are 

















































51 


TOOL DRESSING 


17 


finished by driving into them, from first one side and then the 
other, what is known as a drift pin, that is, a pin of the 
required size and shape. To make the opening the proper 
shape, it is necessary to work the pin, or drift, into the hole 
made by the punch, very carefully, keeping the steel closed 
around the drift during the operation of shaping the hole so 
that the hammer handle may be wedged in it. The stock 
must be hot enough to work freely. 


26. One of the face ends a, Fig. 5, is now drawn out to 
the required form. This end is then held in the tongs while 
the other end is treated in the same manner. The stock is 
next cut apart at c, Fig. 6, and the peen ends are drawn to the 
form and dimensions shown in Fig. 5. Ball-peen hammers and 




r=r 




f v 



Fig. 6 


those having other shapes may be made in nearly the same 
manner. The drawing may be done with a hand hammer, or 
with the fuller and flatter. 


27. A machinist’s or blacksmith’s hammer is usually 
hardened by grasping the peen end in a pair of tongs and 
heating the face end by thrusting it only a little way into the 
fire, turning it frequently. There is danger that the outside 
corners will be overheated before the center of the hammer 
face is hot enough to harden properly. The easiest way to 
avoid this is to heat slowly, though care must be taken not to 
let the heat run too far back toward the eye. Some smiths 
cool the comers of the hammer slightly by dipping them into 
water, holding the hammer nearly flat and revolving the corners 
in the water. The hammer is then replaced in the fire until 
it is brought to the hardening temperature, usually a dull 
red, when it is hardened by dipping the face about \ inch into 
the water, and moving it about quickly with a circular motion. 
The hardness should be tested with a file, both in the center 
and at the comers, and if sufficiently hard the face may be 



































18 


TOOL DRESSING 


51 


brightened with emery paper or a piece of grindstone, and the 
temper drawn to a purple or blue by the heat remaining in the 
body of the hammer. The hammer may then be cooled in 
water sufficiently to arrest the temper-drawing process. The 
same operation is repeated in hardening and tempering the 
peen end of the hammer, care being taken to keep the face end 
cool by sprinkling with water if necessary. The eye of the 
hammer is not hardened. 


LATHE, PLANER, AND SLOTTER TOOLS 

28. Models.—If the best results are to be obtained from 
the tools used in the machine shop, only the best forms should 
be employed for each particular operation; hence, the shop 
superintendent should determine the best forms for the work 
to be done, adopt a set of standards, and three sets of iron 
models of these tools should be forged. One of these sets 
should be ground to the proper form, mounted on a board, 
and retained in the tool room for reference; the other two sets 
of forgings should be mounted on boards, one board being kept 
in the tool room and the other mounted near the tool-dresser’s 
fire. No tool that varies from these forms should be made or 
used except on special written order from the superintendent 
or foreman. 

29. A few typical lathe tools are shown in Fig. 7, a few 
typical planer tools in Fig. 8, and in Fig. 9 some slotting and 
other special tools. Figs. 10 and 11 illustrate charts that are 
furnished with the Sellers’ grinding machine that give the clear¬ 
ance angles for grinding the different tools-. The angles to which 
the various sides of the tools would be forged are somewhat 
larger than those given in order to reduce the amount of grind¬ 
ing required to sharpen the tools. The numbers placed oppo¬ 
site the tools in Figs. 7, 8, and 9 correspond to similar numbers 
on the shanks of the tools in Figs. 10 and 11. In the case of 
the side-finishing planer tools illustrated in Fig. 11, it will be 
noticed that two angles are given for d. The upper angle is the 
top side rake, at right angles to the cutting face, and the lower 
angle is the top rake in the direction of the cutting face. These 




19 


Fig. 7 










































































Fig. 8 


20 

































































































































22 


TOOL DRESSING 


51 


charts and figures are given simply to show what is considered 
good practice in regard to the shape of the tools. 


30. Diamond-Point Lathe Tool.— Suppose the right- 
hand, diamond-point lathe tool shown in Fig. 12 is to be made. 



For a small tool, stock \ inch by 1 inch in section may be 
selected; the length of the stock required would be about 
| inch less than the desired length of the tool. To make the 





















































































































































§51 


TOOL DRESSING 


23 


tool, one end of the stock is squared and a y^-inch bevel e is 
formed on the edges, after which the other end of the stock is 
drawn to the form shown in Fig. 13 (a). This end is next 
drawn to the form shown in (6), after which the edge b is placed 



Fig. 11 


in contact with the face of the anvil, the body of the tool being 
held obliquely across the side, as shown in Fig. 14 (a). A few 
blows are then struck on the uppermost corner of the work. 
The position of the tool is now shifted until the tool is in the 






































































































































































24 


TOOL DRESSING 


51 


position shown in (6), and a few blows are struck on the corner 
now uppermost. The tool is now returned to the first position 
and a few blows struck, after which it is changed again. This 



Fig. 12 


Alltel. 




“Oil!"' 
“Ifi; ''Hlf. 


l-Wlllillii::, 


operation is continued until the end is square in section and of 
the form shown in Fig. 12. The point /, Fig. 13 (6), is next 
cut off at an angle, as shown in Fig. 12, with a sharp cutter, the 
direction of the cut being from d to the opposite comer. The 
point is then bent to one side, as shown. Care must be taken 
not to work the steel at too low a temperature to prevent a 
crack forming at a, Fig. 12. 

The tool is next hardened and the temper is drawn to a 
light straw color for about f inch back from the cutting edge. 
The hardening and tempering are done in the same manner 

as described for the 
cold chisel. 

31. Right-Hand 
Side Tool. —If a 
small right-hand side 
tool, Fig. 15, is to be 
made, a piece of stock 
i inch by 1 inch in 
section may be se¬ 
lected. One end of it 
is then beveled as 
shown at a c, Fig. 16 
(a), the distance from 
a to the end of the 
bar being about If inches. The stock is next placed on the 
anvil so that the corner a is over the rounded edge, the piece 
being held as shown in (6). It is then driven down with blows 
delivered in the direction of the arrows in (c). This will bring 




'«■' *ij:, 

•is.. 



(a) 



(b) 

Fig. 13 









































































































































§51 


TOOL DRESSING 


25 


it to the shape shown in (d)> the edge c d being made thinner 
than the bottom ef. When it is forged to the right thickness, 
the edge and point are 
cut off with a hot cut¬ 
ter to the shape in¬ 
dicated by the dotted 
lines. The edge c d must 
be straight when fin¬ 
ished, and it must be 
above the top of the 
bar so that a number of 
grindings may be made 
before redressing is nec¬ 
essary. After the parts 
are made of the required 
thickness and dimen¬ 
sions, the edge is set over 
to one side in the manner 
shown in ( e ), the piece 
being placed over the 
rounded edge of the anvil and the set hammer used as indicated. 

The temper should be drawn to a dark straw color. Care 
must be taken not to overheat the thin edge, and it is well to 
dip this tool as shown in (/); this leaves the heel a red hot, and 
provides a source of heat for drawing the temper. 

32. When a large number of side tools are to be dressed, it 

is advisable to use 
special swages, one 
form of which is shown 
in Fig. 17. This one 
is used for either right- 
or left-hand side tools. 
When the swage is to 
be used, the stock is 
first beveled as shown 
in Fig. 16 (a), after which the swage is put in the hardie hole, 
and the tools are formed in the swage by the use of a flatter. 













































































































lEi 




iii= 




j i 


L!!u 


jmmk- i 

liiiilllil:'::- 





a d 


(b) 



Fig. 16 



Fig. 17 


26 




























































































































































§51 


TOOL DRESSING 


27 


33. Boring Tool. —To make the boring tool shown in 
Fig. 18 (a), the proper amount of the end is first drawn down 
with the sledge and hammer to the form shown in ( b ). Then 
i inch of the end is placed on the anvil, the shoulder shown 
at a in (c) is formed, and the end is bent to the shape shown 




(a) 




•!! I : ij 



(D 



Fig. 18 


by the dotted lines. The point is next cut to the required 
shape with a sharp hot cutter. 

The tool is tempered to a dark straw color, as was the side 
tool. In most cases, only the cutting edge is left hard, the 
temper being drawn by allowing heat from the body of the tool 
to run to the point. In the case of very long slender tools, the 

I L T 3S2B—11 























































































































































































28 


TOOL DRESSING 


51 


entire length of the drawn-out portion of the tool is sometimes 
hardened to give stiffness to the tool. The neck is then drawn 
to a spring temper by heating over a bar of hot iron. 


FLAT DRILLS 

34. The point of a long-shank flat drill, such as is shown 
in Fig. 19, is made of steel, but the shank is usually iron. To 
weld both parts together, the steel is formed as shown at a, 

Fig. 20, and the iron as 
shown at b. The iron 
is then heated to a red 
heat, the cold steel is 
driven into the cleft, borax is put on the joint, and the iron 
is closed about the steel, after which the work is heated to 
a welding temperature. As the iron forms the outside of the 
joint, the steel is protected from overheating. When heated 
to a welding heat, the pieces are taken from the fire and 
welded together. The shank is then cut to the proper length, 
the end forged square to fit into the brace or ratchet, and the 
point forged to the proper form. 

When forged, the drill is first annealed, next hardened, and 
its temper is then drawn to a full yellow color. The temper 
of the drill may be drawn by the heat in the shank. If the 
shank is not hot enough, a large nut or heavy piece of iron 
having a hole through it may be heated and slipped over the 
shank close to the point, the drill being held so that it does not 



Fig. 20 


touch the hot iron. The heat that radiates from the iron will 
soon draw the temper. A pair of hot tongs is often used for 
drawing the temper, the work being held by the tongs near the 
point of the drill. The heat from the tongs will draw the temper 
of the drill point. When the desired color appears on the point, 
the tool is quenched to prevent further drawing. 



Fig. 19 



































TOOL DRESSING 


29 


§51 


SPRINGS 

35. Making of Spring. —To make a flat spring, like 
the one shown in Fig. 21, a piece of steel is drawn out flat and 



slightly tapered, care being taken to make the taper very 
regular. The flat surfaces are finished with a flatter. The 
steel is then annealed and filed or ground on a stone to remove 
all irregularities and uneven spots. It may then be bent cold 
in the hand, or over the horn of the anvil without hammering; 
or it may be heated and then bent 
into the shape shown. When evenly 
bent it is ready for hardening. 

36. To harden it, the entire spring 
may be slowly and evenly heated in 
an open fire or in a pan of sand. After 
the piece has been raised to a cherry- 
red heat it is cooled in oil or water. 

When cooling the spring, it may be 
held in the tongs and dipped vertically. 

After being cooled, the surface may be 
tested with a file to determine if it is 
hard enough; if not hard enough, the 
hardening process should be repeated. 

37. When hardened, the steel is 
rubbed bright with emery cloth and 
then tempered to a dark blue color. 

The tempering can be done over the 
open fire, or in a sand bath previously 
heated to the proper temperature, or 
over a piece of hot iron. When 
drawn to a dark blue color, the spring is plunged into cold 
water. 



205—11 




































30 


TOOL DRESSING 


§51 


The temper may be drawn by holding the spring over the 
fire and heating it slowly and evenly by moving it back and 
forth, a light draft being used. To know when the spring has 
reached the right temperature, a pine stick, sharpened to a 
point, is rubbed over the surface; when sparks follow the stick 
the right temperature has been reached and the spring is then 
plunged into oil or water. Care should be taken to heat and 
cool the spring evenly and to keep it out of drafts when heated 
in order to prevent it from warping and cracking. 

The temper of springs may also be drawn by a process 
variously known as burning off, flashing off, and blazing off, 
that is described in Hardening and Tempering. 

38. Testing of Spring. —The spring may be tested as 
follows: Its shape is first marked off on the bench or on a sheet 
of paper, then it is clamped in the vise at the 
thicker end and the projecting thin end bent for¬ 
wards and allowed to spring back several, times. 
The spring is then compared with the drawing 
to see whether it has changed its form. If so, it 
is too soft; if it breaks, it is too hard. Or it may 
be clamped in a vise with a piece of iron, as shown 
in Fig. 22, and the distance a measured; it is then 
forced down until the point touches the iron. 
After it is released, if the distance a measures the 
same as at first, it is properly tempered. The 
spring must not be struck or dropped after it is 
tempered, as it might thereby be broken. 


STEELING 

39. Steeling a Pick Point. —The operation 
of welding a steel edge or point on a tool having 
a wrought iron stock is termed steeling. Owing 
to its strength, the cleft weld is generally used for 
this purpose. If the point b of a pick mattock, 
shown in Fig. 23, is to be steeled, the iron is split open, as 
shown at /, Fig. 24, and prepared for a cleft weld. The bar of 






51 


TOOL DRESSING 


31 


Fig. 24 


s 


steel d is then scarfed on both sides, as shown, both pieces 
heated, and then welded together. After this the point of the 
pick is drawn out to the re¬ 
quired shape. Picks, axes, 
adzes, and similar tools, are 
generally steeled in this way. 

40. Steel Facing. —When 
a sheet of steel is welded to 
an iron back, the operation is 
called steel facing. A thick 
piece of steel is frequently 
welded on and the iron and 
steel are then drawn out thin. 

Cutters for wood-planing ma¬ 
chinery are sometimes made 
with steel faces and iron backs. 

The iron i and steel s are first welded together as shown in 
Fig. 25, and then drawn down to the required thickness. 



Fig. 25 


SPECIAL TOOLS 

41. Stone Chisels. —For carving and lettering stone, 
special chisels are used with wooden mallets. They have a 
ball-shaped head, as shown in Fig. 26, and the body is swaged 
down tapering under the head; this lightens the chisel and 
gives it a better balance in the hand. These chisels are made 
of i~> f-> an d f-inch octagonal steel. In making these 
chisels, the pieces of steel are cut off at a proper length for two 
chisels, and the ends of six or eight pieces are placed different 
distances into the fire. The one farthest in the fire will arrive 
at the proper heat first. It is then removed, gripped in a 
vise, and quickly upset by a few blows of a light sledge and the 
blacksmith’s hammer. The hot steel is then removed to a 
hardened-steel die, or swage, d on the anvil shown in Fig. 27. 
This die rests loosely on the face of the anvil, and is held in 
place by the saddle e placed across the anvil. The clamp /, 
fastened with two setscrews, helps to retain the die on the 









































32 


TOOL DRESSING 


§51 


anvil. A top swage g, with a handle about 1 foot long, is also 
used. The ball head of the chisel is formed between the top 

and bottom swages, which also form 
the taper neck under the head, the 
steel being rotated during the oper¬ 
ation. Sometimes there will form 
at the center of the head a small 
teat, which can be knocked off with 
a hot cutter by a single blow of a 
light sledge. By the aid of these 
tools, only a few seconds are re¬ 
quired to form each head, a new 
piece of steel being put into the 
fire at the same time the hot one 
is removed. After the head is 
finished on one end of the steel, the other end of it is placed in 
the fire. When nicely polished swages are used, the chisel 
heads formed have a smooth finish. This is desirable in order 
that the wooden mallet 
used on them may last 
a long time. The center 
of the head is usually 
touched on an emery 
wheel to smooth it. 





0 

l 

x -j 




77? - 




© 

e 




42. After both ends 
are headed, the pieces of 
steel are cut in the mid¬ 
dle and drawn out into 
long, slender wedge- 
shaped chisels. The 
teeth are then marked 
off with a three-cornered 
file, after which they are 
cut while hot with a 
chisel shaped like the 
teeth. Or, a cutter of the desired form may be placed on a 
grinding-wheel arbor and used to saw the teeth of the chisel. 


Fig. 27 


















































































§51 


TOOL DRESSING 


33 


The cutter is made of tool steel. Its diameter may be about 8 
inches and its thickness at the hub about f inch. It is made 
without teeth and is run at a speed of about 2,000 revolu- & 
tions per minute. When the saw is used to cut the 
teeth, they are marked off on the chisel and sawed, the 
chisel being cold. The shape of the teeth depends on 
the material to be cut. For cutting sandstone, the teeth 
should be heavy but not sharp, as shown in Fig. 26. For 
cutting granite, they should be heavy and sharp. For cut¬ 
ting soft marble, they should be light and sharp. 

43. Rock Drills.-—A rock drill, known as the plug 
and feather drill , is shown in Fig. 28. As it is used with 
the hammer, the ball, or mallet head, is not required, and 
the cutting end of the drill has a blunt taper. A special 
fixture h, Fig. 29, is used on the anvil while dressing the 
drill. This consists of a block of steel, about 3 inches FlG ' 28 
square and 1J inches thick, that has a shank fitting the hardie 
hole; this shank is slotted for a key i that holds the fixture 
firmly to the anvil. The top of the block tapers an amount 
equal to half the taper of the drill, and its high side is cham¬ 
fered, as, otherwise, the edge would be likely to chip off. By 
using this fixture and the special hammer shown in Fig. 30, the 

drill may be held level 
while being forged. 
The ends of the ham¬ 
mer have the same 
taper as the top of the 
block. The drill 
should be turned over 
occasionally while be¬ 
ing dressed. 

44. As it is de¬ 
sirable to have a 
hardie and the special 
fixture h, Fig. 29, on 
the anvil at the same time when making rock drills, and as the 
anvil contains but one hardie hole, a special hardie, as that 



Fig. 29 










34 


TOOL DRESSING 


51 


shown at a, may be used. This hardie fits in a square hole 
in a saddle that is clamped to the anvil by means of setscrews. 

Other forms of rock drills are those commonly used by 
miners to drill through rock. In Fig. 31 (a), one form of hand 

drill is illustrated. 
This drill is made of 
octagon steel and is 
forged to the shape 
shown by drawing out 
the end of the steel so 
as to form a cutting 
edge that is a little wider than the stock. In (6), one form of 
machine drill is illustrated. It is forged to the shape shown 
out of special drill stock that has a cross-section of the form 
shown in (c). The parts a, in (6), are first tapered by the use 
of a set hammer, after which the end of the work is heated and 
then shaped with a steel die of the form shown in (d). The 
part b of the die fits in the hardie hole of the anvil. The die 



Fig. 30 




(a) 




Fig. 31 


(d) 


is also made in the form of a flatter or dolly, provided with a 
handle, the grooves being cut in the face. The grooves are 
often made to run clear across the face. In case a die is not 
available, the cutting edges of the tool may be formed bv filing. 






















































































§51 


TOOL DRESSING 


35 


After the drills are forged, they are hardened by heat¬ 
ing their ends for about 1J inches to a cherry-red color 
and then quenching in cold 
water. If the rock to be drilled 
is soft, the temper of the drill 
may be drawn to a light blue 
color; while if the rock to be 
drilled is hard, the temper is drawn to a straw color. 

45. Marble Turning Tools. —For making columns or 
other round work, marble may be readily and rapidly turned 

in a lathe. For such work a different 
form of tool from that used in lathes for 
turning metals is required, and frequent 
dressing is necessary. One form of 
marble turning tool is shown in Fig. 32. 
This tool has a round cutting edge, 
although the cutting edge may be oval, 
square, diamond-shaped, or of any other 
form. The tool shown may be forged 
in the steel die. shown in Fig. 33, which 
has a shank that fits the hardie hole of 
an anvil, the die being used to give the 
proper shape to the nose of the tool. When the dressing is 
finished, the tools are hardened, and then their temper is drawn 
to a straw color. 


HIGH-SPEED-STEEL TOOLS 

46. Forging. —High-speed steel is largely used for lathe, 
planer, and similar tools. It is difficult to forge, and forging 
directions are usually supplied by the steel maker. As a rule, 
the steel should be heated slowly and thoroughly to a full 
yellow heat, care being taken not to heat the steel farther back 
than is necessary to form the tool. The steel should, however, 
be heated back far enough so that no work will need to be done 
on the shank while it is below a cherry-red heat. The heating 
should be uniform and should penetrate to the center of the 
bar. Frequent reheatings are often necessary to make large 














































36 


TOOL DRESSING 


§51 

tools. It is essential that the steel is not worked at lower than 
a bright red heat, to avoid checking and cracking. If heated 
too rapidly, the steel will not flow freely under the blows of the 
hammer and cracks are likely to develop, owing to the stresses 
set up in the steel by the unequal expansion and contraction 
of the exterior and interior parts. 

47. After being properly heated, the steel is forged in the 
usual manner. If a large tool is being formed, the blows should 
be heavy enough so that their effect will extend to the interior 
metal and not be absorbed by the surface alone. If a light tool 
is being formed, the blows should be relatively lighter. The 
forging should be done rapidly, being completed in one heat if 
possible. Tools that require considerable working, however, 
generally require two or three heats, depending on the tool, the 
number of helpers, and whether a power hammer is used. It is 
advantageous to use a power hammer on heavy tools, as better 
results may then be obtained at a lower cost. To remove the 
forging stresses, the tools are reheated to a red heat, after the 
forging is finished, and laid on the floor to cool. 

48. Heat Treatment. — High-speed steels may be annealed 
by packing them in a piece of pipe or an iron box containing 
powdered charcoal, in which the pieces of steel are embedded. 
The pipe or boxes are well sealed with fireclay to exclude the 
air, heated to a bright cherry red for several hours, and then 
allowed to cool slowly. The steel will machine as easily as 
carbon tool steel after it is annealed. 

49. To harden lathe, planer, and similar tools made of 
high-speed tool steel, they must be heated to a fusing, or white, 
heat and cooled in air or oil. At a white heat, the steel is very 
soft and will crumble if struck. It is very necessary to have 
a non-oxidizing fire, which may be obtained in a covered fire 
with a large amount of crushed coke over the tuyere, and using 
a light blast. The steel must not be heated too quickly. 
"When the white heat is attained, a slight fluxing will be observed, 
and as the heat increases numerous small bubbles will be 
seen; then the bubbles become larger and fewer in number. If 
carried to an extreme heat, the steel will soften, a condition 



51 


TOOL DRESSING 


37 


0 


o=o == ra i 


A 


n 


a 


sometimes called sweating. On reaching the sweating point, 
the tools are cooled, usually in a jet of compressed air. One 
method of doing this is 
shown in Fig. 34. The ^ 
tools are placed on an 
iron plate a with a fire¬ 
brick on either side and 
a jet of compressed air 
from a f-inch pipe c is di¬ 
rected against the point 
of the tool. In order to 
insure dry air, the air is 
passed through an iron 
cylinder b about 6 inches 
in diameter and 3 feet 
long, the moisture being 
deposited in the cylinder. 

The supply pipe d is 
1 inch in diameter. It is 
sometimes claimed that *$) 
with this method the tool 
is cooled too far back 
from the point, and that it is therefore better to blow the air 
upwards against the point a of the tool, as shown in Fig. 35. 

50. When the tools are oil hardened, all that is necessary 
is a tank of oil, although in shops where a large amount of 

hardening is done a large tank that is 
equipped with a device for cooling and 
circulating the oil should be provided. 
One form of oil tank is shown in Fig. 36. 
It consists of a sheet-iron casing a, a re¬ 
movable ring b that supports netting c , 
and pipe d through which air is supplied 
to the pipes e. The tank is filled with oil 
to a level indicated by the line /, and air 
under pressure is admitted to the pipes d and e. These pipes 
have a number of small holes in their upper sides through 


Fig. 34 


_ 
















Fig. 35 


205—12 

































































































38 


TOOL DRESSING 


51 



which the air passes and bubbles up to the surface, thus cooling 
and circulating the oil. The supply of air is regulated by the 
valve g, and a small net basket h may be provided into which 
small tools may be dropped to quench them, no further atten¬ 
tion being required. 
The netting c is used 
to prevent the tools 
from dropping to the 
bottom of the tank. 

51. There are 
many different oils 
used for the quench¬ 
ing bath, linseed, cot¬ 
tonseed, fish, whale, 
lard, and kerosene 
being the most com¬ 
monly used. Whale 
and fish oils are prob¬ 
ably the best suited 
for the bath but they 
have offensive odors. 
This disadvantage 
may, however, be 
overcome by mixing 
a little heavy mineral 
oil with them. Lin¬ 
seed oil is inclined to 
be too gummy for 
general use, while 
lard oil becomes 
rancid in time. 
When kerosene oil is 
used, the tools should be plunged quickly to a point above 
the heated portion in order that there will be no flashing, or 
burning of the oil. To avoid oxidation, the quenching must 
be done as soon as possible after the removal of the tool from 
the furnace. 


a 

















o 


o 


Qe Qe Q dQ 


ci 


33T 



Fig. 36 













































































































































§51 


TOOL DRESSING 


39 


52. Rouiid-Nosed Lathe Tool. —One form of round¬ 
nosed tool used to take roughing cuts when turning is shown 
in Fig. 37 (a) as it appears after the forging is finished. This 
tool is made of 1"X1^ // bar stock and is known as a 1-inch 







Fig. 37 

tool. In ( b ), the tool is shown after it has been hardened and 
ground ready for use. In the illustrations, a represents the 
body of the tool; b, the nose; c, the heel; d, the lip surfa.ee; 
e, the cutting edge; /, the clearance angle; g, the back slope or 
top front rake; and h, the side slope or top side rake. 

















































40 TOOL DRESSING § 51 


The nose of the tool is so forged that the clearance angle, 
back slope, and side slope will be greater than the corresponding 
angles of the tool when ground, in order that the amount of 

metal removed when grinding 
may be reduced to a mini¬ 
mum; and the nose of the 
tool is made to extend high 
above the body of the tool in 
order that the tool may be 
reground a large number of 
times before redressing is 
necessary. To avoid the 
tendency of the tool to over¬ 
turn, or rotate to one side, in 
the tool post when taking the 
cut, the nose of the tool is 
set over to one side of the 
tool about 15° as shown at i. 


53. The forging of a 
round-nosed lathe tool 
involves heating the end of 
the stock, bending up the end 
of the bar to form the nose, 
drawing down the heel of the 
tool, shaping the nose with a 
chisel, cutting the nose to the 
correct height and lip angle, 
and setting the nose over to 
one side. In Fig. 38 (a), the 
stock is shown after the nose 
has been turned up on the 
anvil; in ( b ), it is shown with 
the heel drawn down, to give 
support close under the cut¬ 
ting edge; in (c), the nose is shown cut approximately to the 
desired shape, the corners shown in ( b ) having been cut off; and 
in (d), the tool is shown cut roughly to the proper lip angle. 





































51 


TOOL DRESSING 


41 



Fig. 39 


54. To bend up 
the end of the bar 
to form the nose of 
the tool, the bar 
may be clamped to 
the anvil as shown 
in Fig. 39 (a). To 
do this the heated 
end of the bar a is 
laid on the face of 
the anvil so that 
about 2 inches of 
the bar extends be¬ 
yond the edge of 
the anvil; the 
shank b of the 
clamp c is then 
passed through the 
hardie hole, the 
clamp being held 
by the handle d. 
The clamp is now 
drawn tightly 
against the bar by 
forcing a wedge e 
into a hole in the 
shank b. The 
blacksmith and his 
helper next bend 
the work to the 
position shown in 
the illustration by 
the use of sledges. 

In order to test 
the angle to which 
the end of the bar 
is bent, a gauge 
similar to that 










































































































































42 


TOOL DRESSING 


51 



shown in ( b ) may be mounted near the anvil. This gauge is 
merely a small cone /, in this case having an included angle of 
40°, or side angle of 20°, that is fitted into the surface plate g. 
To test the angle to which the end of the bar is bent, the bar 
is removed from the clamp and placed with its bottom surface 
on the plate and the bent surface against the cone as shown. 

If the surfaces of the 
work and the cone 
coincide, the end of 
the bar has been bent 
to the correct angle. 
The tool now appears 
as shown in Fig. 38 (a ). 

55. To draw down 
the heel of the tool to 
secure a good support 
under the cutting 
edge, the tool is 
quickly released from 
the clamp, Fig. 39 (a), 
and, without being re¬ 
heated, removed to a 
steam hammer. The 
heel a of the tool is 
then placed on the 
edge of the anvil, as 
shown in Fig. 40, and 
drawn to a wedge 
shape by a few blows 
of the hammer. If a 
power hammer is not available, the heel may be drawn down by 
sledging upon the anvil. The tool now appears as shown in 
Fig. 38 (6). 


56. To make the nose of the tool of the proper curve, it is 
next laid on the anvil, without being reheated, and its corners 
are then cut off with a chisel as indicated in Fig. 41 (a). The 
bottom of the heel of the tool is now trimmed off flush with the 



















§51 


TOOL DRESSING 


43 


bottom of the bar, a chisel mark is made on the nose of the tool 

to locate the lip sur¬ 
face, and the tool is 
returned to the fire for 
a second heat. The 
tool now appears as 
shown in Fig. 38 (c). 
All the work done on 
the tool so far has 
been in a single heat. 
In case, however, the 
tool should become 
cooled below a light 
cherry color, it should 
be reheated before 
continuing the forg¬ 
ing. When reheated, 
the nose of the tool is 
cut by the use of a 
hot chisel as shown in 
Fig. 41 (6) to form the 
proper lip surface. 
The tool now appears 
as shown in Fig. 38 (d ). 
The nose of the tool is 
next bent over side- 
wise by the use of a 
flatter, after which it 
appears as shown in 
Fig. 37 (a). 

57. After the nose 
is set over, the tool is 
carefully straightened 
so that a good bearing 
surface may be had 
on the bottom of the tool, the clearance angle is then tested 
by the use of the cone gauge, as shown in Fig. 39 (6), and the 




























44 


TOOL DRESSING 


51 



Fig. 42 


lip surface may be tested by the use of a gauge of the form 
shown in Fig. 42. To use this gauge, its shank a is placed on 

the body of the tool 
with the guide b 
against the side of it, 
the gauge being held 
by the handle c and 
the part d being 
placed next the lip 
surface of the tool. 
The outline of the 
cutting edge and the 
angle of the lip surface should be about the same as that of 
the gauge. The tool is next hardened, after which it is ready 
to be ground for use. 

58. Cutting-Off, or Parting, Tool. —Suppose it is 
required to forge the cutting-off, or parting, tool, shown in 
Fig. 43. To make the tool, the end of the stock is first heated 
to a good forging heat, after which it is held on the anvil as 
shown in Fig. 44 (a) and a fuller mark is made in it by the use 
of the fuller a and the sledge b. The tool is next turned over, 
as shown in (6), and it is struck a few blows with the hammer 
and sledge. It is then turned to the position shown in (c) and 
hammered lightly. The tool is turned back and forth to the 
positions shown in (a), ( b ), and (c) while it is being hammered 
to the required length and thickness. The flat sides and edges 
of the tool may be finished quickly by the use of a set hammer or 
flatter, and the final hammering should be done on the cut¬ 
ting edge, or top surface, to smooth the surface so that little 
grinding will be required. 



59. The surplus stock 
is trimmed off the end of 
the tool by the use of a hot 
chisel as shown in Fig. 45 (a ). 

The end clearance angle c, Fig. 43, may be from 15° to 20°, and a 
cone d, Fig. 45 (b), that sets on a surface plate e may be used to 
determine when the required angle is obtained. The end of the 





























































(a) 




45 


Fig. 44 















































46 

































































51 


TOOL DRESSING 


47 


cutting-off tool must be thinner on its bottom than on its top 
edge. A convenient way of testing for this is by using a cylin¬ 
drical gauge /, in (c), that is fitted to the surface plate e. When 
the corners of the top edge of the tool touch the gauge as shown 
in the illustration while the corners of the lower edge do not 
touch it, the tool has side clearance. 

60. Other Forged Tools .—The round-nosed tool described 
is but one form made of high-speed steel. Many other 
forms are in use. In some cases, the nose is made to extend 
higher above the body of the tool, and in others the nose does 
not extend as high. Again, a somewhat different contour of 
the cutting edge and different clearance and rake angles may 
be used. The forms of the various tools shown in Figs. 7 to 11 
are about the same for high-speed-steel tools as they are for 
the carbon-steel tools, as far as the forging of them is con¬ 
cerned. The exact shape and dimensions are usually deter¬ 
mined by each shop, and a chart and models of the desired 
forms made. This chart and the models are used by the smith 
as a guide when forging the tools. 





















• ; 






















